ADC/DAC
المنتجات (3,100+)
ICL7109CPL - 12-Bit ADC Dual-Slide Integrator 40-PDIP | Maxim Integrated
The Maxim Integrated ICL7109CPL is a monolithic 12-bit integrating analog-to-digital converter designed for easy interface with microprocessors and UARTs, housed in a 40-pin PDIP through-hole package. It delivers up to 30 conversions per second, supports differential inputs, and provides binary outputs plus polarity and over-range flags that connect directly to an 8-bit or 16-bit microprocessor data bus. Key specifications include 12-bit resolution, dual-slope integration architecture with a zero-integrator phase added by Maxim to suppress over-range hangover and crosstalk, low input bias current suitable for direct transducer connection, and CMOS power consumption that allows battery or loop-powered data acquisition. The 3-state binary outputs simplify shared-bus multiplexing when one ADC per channel is preferred over an analog multiplexer. The ICL7109 uses the dual-slope conversion principle, in which the input signal is integrated over a fixed period and then de-integrated against an external reference voltage. The resulting count is proportional to VIN/VREF, naturally providing excellent normal-mode rejection at the integration period and inherent input integration. Maxim's zero-integrator phase modification eliminates the residual integrator charge that traditionally caused over-range recovery delay and adjacent-channel crosstalk in multiplexed systems. Typical applications include digital panel meters, weighing scales, industrial process transmitters, remote data acquisition via UART modems, and low-bandwidth precision sensor readouts. The wide common-mode input range and bipolar single-supply operation also suit loop-powered 4-20 mA transmitters and battery-powered instrumentation where CMOS power dissipation is critical. When designing with this device, choose integration capacitors with low dielectric absorption (polypropylene or NPO ceramic) to minimize linearity error, and place reference, integrator, and auto-zero capacitors close to the analog pins to reduce leakage. Using an external low-drift voltage reference such as the ADR01 or REF02 maximizes absolute accuracy. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not commonly found in condensed vendor listings.
ICL7109EPL+ - 12-Bit Dual-Slope ADC | Analog Devices
The Analog Devices ICL7109EPL+ is a 12-bit, single-input, dual-slope analog-to-digital converter with tri-state binary outputs, operating from a -40°C to +85°C industrial temperature range. It uses a 40-pin ceramic dual in-line package with 0.600-inch pin spacing. The converter is designed for low-power data-acquisition systems where direct digital measurement, low input bias current, and a simple parallel output interface are important. An ADC is an analog-to-digital converter, a semiconductor that transforms a continuous analog voltage into a numeric value suitable for processing, measurement, display, or storage. Dual-slope ADCs belong to the integrating ADC family. They integrate an input signal over a fixed interval and compare the result with a reference, producing a proportional digital result. The ICL7109 therefore sits within the broader analog signal-processing and data-conversion hierarchy rather than acting as a general-purpose digital interface or microcontroller. The principal device characteristics are 12-bit resolution, one analog input, dual-slope conversion, and a 30-sample-per-second conversion rate. Its parallel interface can operate in direct mode or handshake mode, while tri-state outputs allow multiple converters to share a bus when appropriate addressing and control are provided. The low input bias current suits high-impedance sources and reduces the loading error that can affect precision measurements. The converter integrates input, reference, and clock functions into a dedicated measurement channel. A zero-integrator phase introduced by the manufacturer helps eliminate overrange hangover, crosstalk, and hysteresis effects during successive measurements. This behavior is particularly useful in multiplexed or repetitive acquisition systems where the converter must settle consistently between readings. The ceramic DIP package supports through-hole PCB assembly and provides a mechanically robust option for established industrial and laboratory instrumentation. Typical uses include digital panel meters, laboratory measurement instruments, process-control interfaces, temperature monitoring, sensor signal acquisition, and low-rate industrial data logging. For a microcontroller-based design, the tri-state outputs can be read through a parallel input interface or port expander. For instrumentation, the reference and input circuitry remain important because accuracy depends on reference quality, input conditioning, clock stability, and the selected integration period. Designers should treat input and reference routing as precision analog signals even though the digital outputs use conventional logic levels. Keep the analog input path short, bypass the supply rails near the device, use a stable reference source, and avoid routing high-current digital outputs beneath sensitive analog nodes. The converter's maximum input voltage and supply limits must also be respected in fault conditions. This product page combines the manufacturer's converter description with engineering-oriented application guidance, package details, replacement analysis, and design notes. It helps evaluators distinguish the ICL7109EPL+ from related converter variants while focusing on practical integration, measurement accuracy, thermal range, and PCB compatibility.
ICL7109EQH - 12-Bit Dual-Slope ADC | Analog Devices
Analog Devices ICL7109EQH is a monolithic 12-bit analog-to-digital converter with one input, dual-slope conversion, and three-state binary outputs in a 44-pin PLCC package measuring 16.59 mm by 16.59 mm. The converter is designed for direct interfacing with microprocessors and UARTs, while polarity and over-range outputs provide additional status information. Analog Devices lists the ICL7109 family as production. An ADC is an analog-to-digital converter, a semiconductor that transforms a continuously varying voltage into a numeric value for processing, measurement, display, or transmission. The ICL7109 belongs to the dual-slope ADC family, a class of integrating converters that measure an unknown input voltage by comparing it against a reference over fixed integration and conversion intervals. This architecture is suited to precision measurement systems where predictable behavior and direct digital output are more important than very high conversion speed. The ICL7109 provides 12-bit binary resolution, one analog input channel, dual-slope conversion, and three-state outputs. Its polarity and over-range outputs extend the basic conversion result by indicating sign and excessive input conditions. For remote data-logging systems, the three-state output arrangement allows multiple converters to share a bus when inactive outputs can be placed in a high-impedance state, reducing wiring and interface complexity. The converter's digital interface is designed around microprocessor control using chip select and two byte-enable inputs. This architecture permits the controller to read 12-bit binary results and associated status flags. The ICL7109EQH is identified in the 44-PLCC package, while the exact input range, reference voltage, conversion timing, and electrical limits must be selected from the manufacturer data sheet and confirmed against the specific ordering suffix before circuit design. Typical uses include digital panel meters, temperature measurement, process monitoring, laboratory instrumentation, and remote data acquisition. The 12-bit result supports 4096 numerical codes, making the device suitable for systems that need moderate measurement resolution rather than high-speed waveform capture. A dual-slope ADC is particularly appropriate when the input changes more slowly than the conversion interval and accurate, stable readings are required. Designers should verify the ordering suffix, supply arrangement, input common-mode range, reference requirements, and timing diagram before assigning the converter to a PCB. Because the package is a leaded PLCC rather than a fine-pitch surface-mount package, assembly planning should include socket availability, lead straightness, thermal exposure, and soldering-process controls. External reference and input filtering should follow the manufacturer application guidance to preserve measurement accuracy. This product summary combines the manufacturer architecture description with distributor package and ordering information. It also identifies pin-compatible family options, clarifies where package and suffix differences matter, and adds practical guidance for interfacing, measurement, assembly, and replacement decisions beyond a basic catalog listing.
ICL7109IPL+ - 12-Bit Dual-Slope ADC | Analog Devices
Analog Devices ICL7109IPL+ is a 12-bit microprocessor-compatible analog-to-digital converter with one input, dual-slope conversion, and three-state binary outputs, packaged in a 40-pin PDIP. The converter is designed for low-cost, low-power data-acquisition systems that require one dedicated conversion channel instead of a multiplexed analog front end. An integrating ADC is a voltage-to-digital conversion category that measures input voltage through repeated integration and de-integration cycles. Dual-slope conversion averages the input over time, making it well suited to low-bandwidth measurements where noise rejection and predictable conversion behavior are more important than very high sampling rates. The ICL7109 occupies a position within the broader ADC, data-converter, and semiconductor hierarchy. The primary device characteristics include 12-bit resolution, one analog input, dual-slope conversion, microprocessor-compatible parallel outputs, and three-state output capability. Three-state outputs permit multiple devices to share a bus when their output drivers are disabled. The low-power operating approach and low input bias current also make the converter useful in instrumentation arrangements where analog multiplexing would otherwise add leakage and crosstalk concerns. The ICL7109 uses a zero-integrator phase to reduce overrange hangover, crosstalk, and hysteresis effects between conversions. This behavior is particularly useful in multi-channel measurement systems that use separate converters for sensitive channels. The 40-pin PDIP package favors through-hole construction, thermal robustness, and straightforward prototyping rather than compact surface-mount assembly. Typical applications include digital voltmeters, process-control instrumentation, laboratory measurement equipment, weighing systems, temperature bridges, and low-rate sensor acquisition. It is especially appropriate when the input signal is slow-changing and a dedicated low-power conversion channel is preferable to a high-speed multiplexing ADC. Designers should follow the Analog Devices ICL7109 datasheet for reference voltage, input range, conversion timing, output-code interpretation, and external-component requirements. The zero-integrator phase must also be considered when calculating measurement-cycle timing, because it affects the interval between completed conversions and the behavior following an overrange event. This page combines the manufacturer product information with practical selection guidance, a structured comparison against a documented converter alternative, and design-focused explanations of conversion timing, bus interfacing, input behavior, and package considerations. These engineering-oriented details help distinguish the ICL7109 from faster SAR converters, multiplexed ADC systems, and general-purpose digital interface devices.
ICL7116CJL - 3.5-Digit LCD Display ADC | Maxim Integrated
The Maxim Integrated ICL7116CJL is a 3.5-digit dual-slope analog-to-digital converter with an integrated liquid-crystal display driver, supplied in a 40-pin ceramic dual in-line package. It is designed for digital-panel measurement systems that require conversion, display hold control, and direct LCD segment drive in one through-hole component. The package is a 40-CDIP, and the device is associated with the commercial temperature grade. A dual-slope analog-to-digit converter is a sigma-delta-style measurement architecture that integrates an unknown input voltage over a fixed interval and then measures the time required for a reference ramp to balance the result. In the ICL7116, this measurement method supports a stable digit-oriented output intended for panel meters, laboratory instruments, counters, and other display-oriented measurement equipment. The ICL7116CJL combines a 3.5-digit A/D conversion function with a display driver and display hold capability. Integrating these functions reduces the number of separate devices required in a digital instrument. The converter output can be used with the associated segment-driver circuitry to present a measured value directly on an LCD panel, making the device especially relevant to compact, panel-mounted meter designs. This IC belongs to the ADC/DAC category within integrated circuits and implements the broader hierarchy of data-acquisition IC, display interface, and display-driver functions. Its dual-slope architecture, 3.5-digit measurement format, and dedicated display-driver outputs distinguish it from general-purpose flash, SAR, and high-resolution pipeline ADC families. The 40-pin CDIP construction also favors leaded industrial and laboratory assemblies rather than compact surface-mount production. Typical uses include digital panel meters, handheld test instruments, counters, laboratory measurement equipment, process-monitoring displays, and educational measurement products. The integrated display function is particularly useful when a numeric result must be read directly rather than converted to another bus format or processed by a separate display controller. When laying out a new board, preserve the pin arrangement and bypass requirements of the ICL7116 family reference circuit rather than treating the LCD outputs as ordinary general-purpose logic. Confirm LCD segment characteristics, reference-source stability, input range, and timing against the manufacturer datasheet before releasing production artwork, especially where the ceramic package is exposed to temperature extremes or mechanical vibration. This product page consolidates the confirmed ICL7116CJL identity, package information, lifecycle considerations, technical alternatives, application guidance, and design notes into one engineering reference. It also distinguishes verified drop-in options from alternatives that require pinout, electrical, or package validation before substitution.
ICL7116CMH - 3.5-Digit ADC with Display Hold | Analog Devices
The Analog Devices ICL7116CMH is a monolithic 3.5-digit analog-to-digital converter with a display hold function, production status, and integrated support for seven-segment display systems. The converter is designed for panel-meter and digital-instrument applications in which a measured value must be converted, decoded, and displayed while retaining a readable hold state. An ADC is an interface IC that converts an analog voltage into a digital numerical representation. The ICL7116 belongs to the family of low-power BCD and seven-segment display converters, combining an analog-to-digital conversion stage with seven-segment decoders, display drivers, an internal reference, and a clock. This integration reduces the component count and simplifies the design of digital voltmeters, temperature meters, process monitors, laboratory instruments, and compact industrial measurement panels. The ICL7116 family provides a hold pin that can freeze or retain the current reading. This feature is useful when an operator must inspect a value that changes continuously, when a measurement must remain stable while another control action occurs, or when the displayed result needs to be copied before the input changes again. Unlike a generic numeric ADC, the device is optimized to drive multiplexed seven-segment displays directly. The converter uses a 3.5-digit measurement format, allowing a display range that includes a sign position and full-scale digit. Its integrated reference, clock, decoders, and drivers place the signal chain and display interface in one package. The manufacturer describes the ICL7116 as a 3.5-digit ADC with display hold, distinguishing it from related converters through the added hold capability. Typical applications include digital panel meters, laboratory readouts, temperature-monitoring instruments, process-control displays, bench power meters, and compact consumer or industrial measurement equipment. In each case, the analog sensor output is conditioned into the converter input range, converted to a digital value, and presented on one or more seven-segment displays. Design considerations center on input signal conditioning, reference stability, display drive requirements, and correct handling of the hold input. The analog input must remain within the device's specified operating limits, while component tolerances around the measurement path can affect displayed accuracy. The manufacturer datasheet should be used to confirm the exact package pinout, pin functions, supply limits, timing, and recommended application circuit before PCB release. This product page combines the confirmed ICL7116 family features with practical selection guidance, complete pinout caveats, sourcing paths, and a qualification-focused comparison framework. It is intended to help engineers determine whether the ICL7116's integrated display architecture and hold function fit a measurement instrument before committing the board layout.
ICL7116CPL+ - 3.5-Digit LCD ADC with Display Hold | Analog Devices
Analog Devices ICL7116CPL+ is a 3.5-digit monolithic integrating analog-to-digital converter with display hold, direct LCD output, and a 40-pin PDIP package. The device provides very high input impedance, supports differential and single-ended 0 V input operation, and uses a dual-slope conversion technique that automatically rejects interference common in industrial environments. An integrating ADC converts an unknown analog voltage into a time-based digital result. In the ICL7116 family, the dual-slope architecture supports high input impedance, good rejection of periodic interference, and direct multiplexing of LCD segment outputs. The display-hold feature distinguishes the ICL7116 from related ICL7106 devices by allowing a measurement to be frozen while the display remains visible. The principal functional characteristics visible in the verified product data are 3.5-digit resolution, direct LCD display drive, display hold, very high input impedance, differential and single-ended operation, and a 0 V input reference. These characteristics make the converter appropriate for panel meters, laboratory instruments, process monitoring, and industrial measurement systems where an operator must view a stable numerical reading. The ICL7116 uses a dual-slope measurement technique rather than a successive-approximation architecture. Dual-slope integration averages the input over a controlled interval, helping reject periodic interference and reducing sensitivity to short-duration disturbances. The Hold pin can freeze the displayed result, while the integrated display-driver outputs reduce the need for separate digital-to-analog conversion or display multiplexing hardware. Typical uses include digital panel meters, temperature-controller front panels, laboratory counters, process-monitoring equipment, weighing systems, and portable instruments. A design using the ICL7116CPL+ should preserve its high-impedance analog input path, provide the external components and display arrangement required by the manufacturer datasheet, and account for the stated 0°C to 70°C operating-temperature range. The principal design trade-off is integration time versus measurement responsiveness. Integrating conversion improves rejection of interference but does not provide the rapid sampling of a high-speed successive-approximation converter. The Hold function is valuable when intermittent readings need to remain visible for observation or copying without changing the underlying converter architecture. This page combines verified manufacturer and distributor information with practical selection guidance, commercial pricing references, package details, and a clear explanation of the ICL7116CPL+ display-hold function. It also distinguishes verified replacements from merely similar converter functions so engineers can avoid assuming that an LCD driver, LED driver, or different conversion architecture is pin-to-pin compatible.
ICL7117CMH 3½-Digit ADC | Maxim Integrated | 44-Terminal QFP
The Maxim Integrated ICL7117CMH is a three-and-a-half-digit ADC with display hold, offered in a 44-terminal gull-wing QFP package. The verified product information identifies the device as an integrated circuit for data acquisition and ADC/DAC applications. Its package is specified as square, with 44 terminals, a 0.8 mm terminal pitch, and package dimensions of 10.0075 mm width and length. The ICL7117CMH designation is associated with Maxim Integrated products documented as ICL7117CMH and ICL7117CMH+ listings. An ADC is an analog-to-digital converter, a semiconductor that converts an analog input voltage into a digital representation. The ICL7117CMH belongs to the broader data-conversion and signal-processing hierarchy, where precision measurement systems commonly combine an analog input, a conversion engine, digital control or processing, and a display or communications interface. The display-hold function is intended to preserve a measured value so it can be viewed or transferred before the next conversion sequence changes the displayed result. The package information is the most concrete differentiator for PCB design. A 44-terminal gull-wing QFP provides external connections for power, analog input, digital output, reference, control, and display-related functions, subject to the exact pin assignment in the manufacturer datasheet. Its 0.8 mm terminal pitch allows a compact square surface-mount footprint, while the 10.0075 mm package dimensions require PCB land patterns and courtyard planning based on the manufacturer drawing. The QFP format also provides mechanical lead support and is generally more convenient for automated board assembly than a fine-pitch leadless package. ICL7117CMH is appropriate for panel meters, laboratory instruments, industrial monitoring equipment, digital weighing systems, process measurement, and other applications requiring a dedicated display-oriented ADC. In these systems, the converter accepts a conditioned analog signal, performs conversion, and presents a stable numerical result. The external circuitry normally defines the input range, reference voltage, integration timing, and display interface behavior. Designers should follow the Maxim ICL7117CMH datasheet for pinout, electrical limits, recommended input and reference networks, timing, and decoupling. Because the verified information does not state the complete electrical ratings, verify the converter resolution, input voltage range, reference arrangement, operating temperature range, supply requirements, and timing values against the manufacturer document before releasing a PCB or production design. This product page combines the verified package and product identity information with practical integration guidance, application mapping, and comparison context. It is intended to help engineers locate the correct ICL7117CMH documentation, understand the package implications, and plan a PCB or replacement review without treating general ADC characteristics as guaranteed ICL7117CMH specifications.
ICL7117CPL+ - 3.5-Digit Dual-Slope ADC | Maxim Integrated
The Maxim Integrated ICL7117CPL+ is a 3.5-digit, low-power, dual-slope analog-to-digital converter with integrated display drivers, a reference, a clock, and a display Hold function. The device is packaged in a 40-pin PDIP and directly drives an instrument-size LED display. Its integrating architecture and very high input impedance suit precision measurement systems that need stable digital readings from relatively high source impedance. An integrating ADC such as the ICL7117CPL+ converts an analog input voltage into a digital result through repeated integration and reference measurement. This dual-slope method is well suited to meters and panel instruments because it provides high input impedance, rejects periodic interference, and can use simple passive input networks. The ICL7117 family adds a Hold pin to the ICL7106 and ICL7107 function, allowing a measured value to remain displayed for examination or transfer to another system. The ICL7117CPL+ integrates a 3.5-digit A/D converter, seven-segment LED display drivers, an internal reference, and a clock. Those functions reduce the number of external components required for a standalone display instrument. The Hold function is particularly useful when an operator must freeze a reading during calibration, inspection, or process monitoring without interrupting the ongoing measurement. The dual-slope conversion method supports rejection of interference at the conversion frequency. Its high input impedance also reduces loading of the sensing circuit, which is important when the input originates from bridges, thermocouples, or other relatively high-impedance sources. The exact conversion timing, input limits, resolution detail, reference voltage, and operating-temperature limits must be selected from the manufacturer data sheet when defining a production design. Typical uses include digital panel meters, laboratory instrumentation, process monitoring, temperature measurement, laboratory scales, and general-purpose industrial measurement panels. The integrated LED drivers make the ICL7117CPL+ particularly appropriate for displays built from conventional seven-segment LED digits rather than multiplexed glass LCDs. An ICL7116CPL+ is the corresponding LCD-oriented family member, while the ICL7117CPL+ supports LED display systems. Designers should preserve the recommended input and reference network, bypass placement, and display-driver layout described by Maxim Integrated. Because this is a through-hole PDIP device in a 40-pin package, PCB allocation must reserve the full footprint and adequate insertion clearance. Power, ground, reference, analog input, timing, and display-driver connections should be assigned directly from the package pin-description table and datasheet application example. This page combines the device architecture, display-function selection, practical layout guidance, package information, and same-footprint replacement analysis. It is intended to help engineers determine whether the ICL7117CPL+ provides the required LED display drive and Hold behavior without adding a separate ADC, display driver, clock, and reference to a measurement instrument.
ICL7117CQH - 3.5-Digit Dual-Slope ADC | Maxim Integrated
Maxim Integrated ICL7117CQH is a 3.5-digit monolithic dual-slope analog-to-digital converter with a parallel word output, built-in reference, bipolar input, and low-noise front end. It operates from a 6 V to 9 V supply in the commercial 0 °C to 70 °C temperature grade and is packaged in a 44-pin PLCC (QCCJ) surface-mount package. The converter is designed to directly drive seven-segment LED displays while providing a held digital measurement when the Hold function is asserted. An integrating analog-to-digital converter converts an unknown input voltage into elapsed time by charging and discharging an internal integration network. The ICL7117 belongs to the integrating ADC, dual-slope ADC, and precision measurement converter hierarchy. Unlike a successive-approximation ADC, a dual-slope converter rejects a substantial amount of periodic noise and is commonly used with panel meters, laboratory instruments, scales, and industrial measurement equipment. Principal characteristics include 3.5-digit measurement resolution, a reported 16-bit conversion word, single-channel operation, parallel word access, an integrated reference source, and support for bipolar input signals. The ICL7117 differs from the ICL7116 because it includes a Hold input and directly supports LED displays, whereas the ICL7116 is intended for LCD displays. This distinction makes pin and function compatibility with the ICL7116 unsuitable despite their shared converter heritage. The internal architecture combines a precision reference, comparator, integrator, timing section, digital counter, and display-driver outputs. Dual-slope conversion repeatedly measures input and reference intervals, producing a result that is effectively proportional to the ratio between the input voltage and the reference voltage. The reported 16-bit parallel output permits a host processor to capture the converted value without reproducing the internal counter timing, while the Hold input can freeze the displayed result during measurement or interface transactions. Typical uses include digital panel meters, laboratory measurement instruments, process-monitoring equipment, weighing systems, and embedded instrumentation with discrete LED displays. The 6 V to 9 V supply range suits systems that already provide a 9 V rail, while the commercial temperature grade targets indoor laboratory, industrial, and commercial equipment operating between 0 °C and 70 °C. Designers should pay particular attention to input polarity, reference accuracy, integration timing, display-driver compatibility, and the distinction between the Hold and Digit inputs. Confirm the complete QCCJ pin assignment and board footprint against the manufacturer data sheet before routing a replacement PCB or connecting LED segments. This product record combines the manufacturer's converter description with package, temperature, interface, and lifecycle information, then adds practical selection guidance and a package-focused comparison for engineers evaluating replacements without requiring a PCB change.
ICL7126CPL+ - 3.5-Digit Dual-Slope ADC | Analog Devices
The Analog Devices ICL7126CPL+ is a low-power 3.5-digit dual-slope analog-to-digital converter with a 3 conversions-per-second conversion rate, integrated seven-segment decoders and display drivers, a voltage reference, and a clock circuit in a 40-pin PDIP package. The converter combines a complete measurement signal chain on one CMOS IC and directly supports a non-multiplexed LCD display. An integrating ADC such as the ICL7126 converts an analog input into a time-proportional digital result by repeatedly integrating the input and measuring the interval required to return to zero. Within the broader semiconductor hierarchy, the ICL7126 is a dual-slope ADC, which is an ADC, which is a data-conversion IC within integrated circuits. This makes it suitable for compact panel-meter and laboratory instrumentation designs where the display driver functions are useful. The principal verified features include 3.5-digit measurement resolution, a 3-SPS conversion rate, low power operation, a 40-pin PDIP package, and integrated segment decoders and drivers. The integrated voltage reference and clock reduce the number of external support circuits needed for a basic digital panel meter. The device also contains the active components required to implement a complete measurement system rather than operating only as a numeric converter. The ICL7126 uses a dual-slope conversion method, integrating both the unknown input and a known reference during successive measurement intervals. Its architecture is intended for high-input-impedance measurement systems. According to the Analog Devices product page, the monolithic converter directly drives a non-multiplexed LCD, while the Renesas datasheet identifies the ICL7126 as a plug-in replacement for the ICL7106 when only passive components are changed. Typical uses include digital panel meters, laboratory meters, process monitoring equipment, temperature and pressure instrumentation, and other low-rate measurement systems with a three-digit display. The integrated display drivers are especially useful when the measured quantity must be presented locally without requiring a separate display controller, microprocessor, or complex display multiplexer. The principal design consideration is that the analog front end, reference network, timing components, and LCD interface must be evaluated together rather than as independent blocks. Grounding, input filtering, reference stability, LCD contrast, and conversion timing determine whether the complete meter achieves useful accuracy. Designers should follow the manufacturer application guidance and verify the exact electrical limits against the current datasheet before finalizing component values. This product page consolidates verified manufacturer information, distributor availability, package details, replacement guidance, and engineering-oriented application guidance. It also distinguishes the verified ICL7126 family information from replacement candidates whose individual electrical ratings still require engineering confirmation against the latest manufacturer datasheets.
ICL7126CQH - 3.5-Digit LCD A/D Converter | Analog Devices
Analog Devices ICL7126CQH is a low-power, 3.5-digit successive-approximation A/D converter designed for direct interface with liquid-crystal displays. The device provides seven-segment display decoding and display-driver functions in a 44-lead J-lead ceramic LCC package. It combines an A/D converter, internal reference, clock, seven-segment decoders, display drivers, and associated control functions on one CMOS integrated circuit. The ICL7126CQH belongs to the ADC/DAC category of signal-conversion semiconductors. An A/D converter, also called an analog-to-digital converter, transforms a continuously varying analog voltage into a numeric code suitable for measurement, display, control, or data acquisition. A 3.5-digit converter can resolve approximately 1999 principal counts and is commonly used for panel meters, laboratory instruments, industrial readouts, and portable measurement systems where more resolution than a simple three-digit display provides is useful. The manufacturer describes the ICL7126 family as a low-power device intended to drive liquid-crystal displays directly. Its integrated seven-segment decoders reduce the external logic required between the conversion result and the LCD. Direct LCD drive simplifies instrument construction by limiting the main external circuitry to the input network, timing components, display connections, and normal bypass or protection components described in the manufacturer data sheet. The ICL7126CQH is specified in the 44-LCC J-lead package and appears on the manufacturer's product page as a production product. Analog Devices also recommends the ICL7136 for new designs, which is an important lifecycle consideration when selecting between continued use of an established converter and migration to a newer family member. The exact electrical limits, conversion timing, input impedance, reference characteristics, display-drive specifications, and environmental ratings should be taken from the ICL7126 manufacturer data sheet before release of a production circuit. Common uses include digital panel meters, digital multimeters, laboratory measurement instruments, temperature controllers, process-monitoring displays, weighing systems, and portable data-acquisition equipment. The integrated display path is particularly useful where designers want a numeric readout without adding a separate display decoder or driver IC. When designing around the ICL7126CQH, begin with the manufacturer pin-description table and application information rather than assigning signals by function alone. Confirm the LCD glass segment mapping, input-source range, reference arrangement, timing components, and bypass requirements directly against the data sheet. Also evaluate the suggested ICL7136 before committing to a long-lived design if the project is newly started. This page organizes the verified package, display, resolution, interface, lifecycle, and sourcing details into an engineering-focused format. It also separates confirmed attributes from parameters that require direct comparison against the manufacturer data sheet, helping designers assess fit before committing the 44-LCC footprint to a PCB layout.
ICL7126IPL+ - 3.5-Digit CMOS ADC | Maxim Integrated
The Maxim Integrated ICL7126IPL+ is a low-power, 3.5-digit successive-approximation A/D converter with an integrated voltage reference and clock, supplied in a 40-pin PDIP package. The converter is designed for low-power measurement systems and uses a differential input architecture with a resolution of 0.05 percent. The ICL7126IPL+ is the commercial-temperature, through-hole version of the ICL7126 family, with an operating range of 0°C to 70°C. An ADC is an interface component that converts an analog voltage into a numeric value for measurement, control, or display. The ICL7126 integrates the active circuitry required for a complete 3.5-digit measurement channel on one CMOS IC. Unlike discrete meter designs, its integrated reference, clock, and conversion system reduce component count while retaining direct measurement of slowly changing voltages. Key features include a true differential input and reference arrangement, a guaranteed zero reading for a zero-volt input, and true polarity at zero for precise null detection. The converter also provides approximately 1 pA typical input current. Its 3.5-digit architecture supports instrumentation displays and panel-meter applications where four digits of resolution are useful while a sign indicator improves readability around the zero point. The CMOS implementation emphasizes low operating power, making the device suitable for portable instruments and battery-operated measurement panels. Integration of the reference and clock simplifies board design by reducing the number of external timing and calibration components. Differential measurement can also reject common-mode voltage when the source and reference paths are arranged carefully, although real-world accuracy still depends on input filtering, reference quality, grounding, and analog-layout discipline. Typical uses include digital panel meters, laboratory measurement instruments, temperature and process monitoring, portable test equipment, and low-power sensor interfaces. The 40-pin PDIP package favors through-hole assembly, repairable prototypes, and larger industrial control boards where a surface-mount footprint would offer little practical benefit. Designers should verify the complete electrical limits and recommended operating circuit in the manufacturer datasheet before release. Pay particular attention to input and reference polarity, conversion timing, bypass-capacitor placement, and the relationship between source impedance and accuracy. A stable, low-noise reference path and short analog traces are essential for repeatable measurements. This product page combines the manufacturer product information with package-specific identification, application guidance, verified sourcing information, and drop-in replacement analysis. It also highlights the practical advantages and limitations of the 40-pin PDIP format for engineers deciding whether the ICL7126IPL+ fits an existing measurement-instrument design.
ICL7129CPL - 4.5-Digit LCD ADC | Intersil | 40-Pin PDIP
Intersil Corporation ICL7129CPL is a 4.5-digit single-chip analog-to-digital converter that directly drives a multiplexed liquid-crystal display. The device combines successive-integration conversion, a precision reference input, and LCD segment-driver circuitry in a 40-pin PDIP package. It is intended for high-resolution measurement instruments where a stable digital reading and direct LCD presentation are required without a separate display driver. An LCD analog-to-digital converter is a specialized mixed-signal component that converts an analog input voltage into a numeric code and presents that code on a multiplexed LCD. The ICL7129 belongs to the broader ADC hierarchy while specializing in direct LCD instrumentation. Compared with general-purpose ADC systems, this integrated approach reduces the number of external components and simplifies the relationship between the conversion engine, digit and segment outputs, and the display. The ICL7129CPL provides 4.5-digit measurement resolution and uses the ICL7129 family's successive-integration conversion technique. The associated ICL7129A documentation identifies approximately ±20,000-count resolution, which supports fine readings in handheld meters and laboratory instruments. Direct LCD drive, CMOS construction, and a 40-pin dual in-line package make the device suitable for conventional through-hole instrument designs. Technical operation centers on the integrated successive-conversion loop, reference voltage, input stage, and display multiplexing. Only passive components and an external reference are needed for normal operation. Because the LCD outputs belong to the same package as the converter, segment-drive timing, reference stability, input filtering, and grounding directly influence displayed accuracy. The converter must also be matched to the selected LCD segment count and operating scheme. Typical uses include handheld digital multimeters, laboratory panel meters, industrial process indicators, temperature instruments, weighing displays, and general-purpose measurement panels. The device is particularly appropriate when a dedicated LCD and a 4.5-digit presentation are central to the product. It can also serve in legacy or repair applications where preserving the established 40-pin PDIP footprint and LCD interface is more important than adopting a newer display architecture. Designers should follow the manufacturer's pin-description and typical-application diagrams when assigning the reference, analog input, conversion-control signals, and LCD outputs. Keep the analog input and reference paths away from LCD drive traces and switching nodes, and place filtering or protection components close to their corresponding pins. Confirm LCD compatibility, reference voltage, timing, and grounding before releasing a new PCB. This product summary combines the ICL7129CPL identification, package information, converter architecture, display use cases, and drop-in family options into an engineering-focused reference. It also highlights the component-selection checks that matter when replacing a 4.5-digit LCD measurement front end without changing the existing through-hole board layout.
ICL7135CAI+ - 4.5-Digit Dual-Slope ADC | Analog Devices
The Analog Devices ICL7135CAI+ is a high-precision, monolithic 4.5-digit dual-slope analog-to-digital converter with a 2.0000 V full-scale capability and accuracy specified to ±1 count in 20,000. It accepts high-impedance differential inputs and provides multiplexed BCD outputs for driving a display in the 28-SSOP package. The converter combines reliable dual-slope conversion with a 0.5-count resolution increment. A dual-slope ADC is an integrating analog-to-digital converter that measures input voltage by comparing a controlled integration period with a reference-driven de-integration period. This technique belongs to the wider ADC, data-converter, and semiconductor hierarchies. It is especially useful when low-frequency measurements require good noise rejection and predictable behavior with slow-changing sensor signals. The ICL7135CAI+ provides a 4.5-digit measurement range, a 2.0000 V full-scale capability, and ±1 count in 20,000 accuracy. Its high-impedance differential input structure supports source impedances that would otherwise degrade simple resistive divider measurements. Multiplexed BCD outputs reduce the number of connections required when driving a seven-segment display, while the 28-SSOP format supports compact panel-meter and laboratory-instrument layouts. The manufacturer describes the ICL7135 as a monolithic converter designed around a dual-slope conversion architecture. Differential input handling is central to its measurement behavior because it permits a sensor signal to be measured relative to a return or reference node. The 4.5-digit result format supports a maximum reading of 19,999 counts, while the stated ±1-count-in-20,000 accuracy establishes the conversion-error target for the product family. Typical uses include digital panel meters, temperature measurement instruments, laboratory readouts, process monitoring, portable meters, and industrial measurement equipment. The device is particularly appropriate when a regulated reference, controlled input excitation, and a dedicated display interface are available. It is less suitable for high-speed waveform acquisition, communications, or applications requiring many conversions per second. For implementation, follow the manufacturer pin-description and application tables when assigning the reference, integrator, input, clock, and display signals. Stable reference and input components are central to repeatable dual-slope measurements, while correct grounding and protection are necessary when external sensors connect to the measurement terminals. This product record combines the official ICL7135 product information with distributor package, ordering, and availability details. It also distinguishes the closely related ICL7135CAI- temperature-grade variant from the ICL7135CMH-D, which uses a different 44-pin package, so engineers can assess replacement options without treating package-incompatible parts as drop-in substitutes.
ICL7135CN 4.5-Digit Precision ADC | Texas Instruments
The Texas Instruments ICL7135CN is a 4.5-digit precision dual-slope analog-to-digital converter with one differential input, 0.003 kSPS conversion rate, multiplexed BCD output, and a 2.0000 V full-scale capability in a 28-pin through-hole DIP package. The supplied distributor data identifies it as a display-driver ADC with ±1 count in 20,000 accuracy and high-impedance differential inputs. What is a dual-slope ADC? A dual-slope ADC integrates an unknown input for a fixed interval and then measures the time required for a reference to return the integrator toward zero. This method is well suited to precision measurement because it rejects periodic noise, averages short disturbances, and can provide high effective resolution with relatively simple analog circuitry. ICL7135CN belongs to the analog-to-digital converter, data-converter, and signal-measurement semiconductor hierarchy. Key features include 4.5-digit BCD-oriented measurement resolution, 2.0000 V full scale, multiplexed BCD output, true differential input, precision zero reading for a 0 V input, and precision null detection with true polarity at zero. The converter is intended for instrumentation applications where repeatable readings and direct display-driver compatibility matter more than high conversion throughput. Its dual-slope architecture favors noise rejection over sampling speed. The ICL7135CN integrates a successive approximation and dual-slope conversion approach according to the verified product descriptions. The external reference and input arrangement must be selected to match the intended measurement range, while the display interface is organized for multiplexed BCD output. Because the supplied search results identify a 28-pin DIP package, the physical design should use the appropriate through-hole footprint and pin assignments shown in the manufacturer documentation. Typical applications include digital panel meters, laboratory instruments, weighing systems, temperature measurement bridges, industrial process monitors, and precision test equipment. These systems benefit from the 4.5-digit readout, differential input capability, and ability to present decimal-aligned BCD results directly to display-driver circuitry. The relatively low conversion rate is suitable for continuously updated measurements rather than waveform acquisition or high-speed data logging. Designers should pay particular attention to reference stability, input impedance, integrator components, timing accuracy, bypass capacitors, and display-drive timing. Use the manufacturer datasheet for the complete electrical limits and pinout, and verify the zero-input and null-detection behavior during calibration. This page combines verified distributor descriptions with engineering guidance while avoiding unverified electrical values that are not present in the supplied data.
ICL7135CPI+ 4.5-Digit BCD ADC | Maxim Integrated
The Maxim Integrated ICL7135CPI+ is a 4.5-digit, BCD-output analog-to-digital converter with multiplexed display outputs in a 28-pin plastic DIP package. It combines dual-slope conversion reliability with an accuracy of ±1 count in 20,000 and a full-scale range of 2.0000 V. The differential input architecture supports measurement systems requiring high input impedance and rejection of common-mode interference. A dual-slope integrating ADC is a signal-conditioning and conversion category that averages an unknown voltage over a fixed integration interval and compares the result with a reference. Within the broader hierarchy, the ICL7135CPI+ is an analog-to-digital converter, an integrated data-conversion circuit, and a semiconductor intended for precision measurement and display instrumentation. Dual-slope conversion is especially useful when resistance, temperature, or slow-changing sensor signals are converted into stable numerical readings. The principal feature set includes 4.5-digit resolution, multiplexed binary-coded decimal outputs for four digit-drive positions, and high-impedance differential inputs. The ±1-count-in-20,000 accuracy specification provides a useful figure for panel meters and digital voltmeters. Its 2.0000 V full-scale capability lets the designer define the measurable range with an external reference. The multiplexed BCD architecture reduces the number of dedicated output signals required to drive a visual display. Technically, the converter separates its analog and digital functions. The analog section develops an integrated representation of the differential input, while the digital section contains counters, timing control, input interfaces, output interfaces, and the logic that coordinates each measurement cycle. This integrating approach favors noise rejection and repeatable readings when the input changes slowly, although conversion time is longer than with a high-speed successive-approximation ADC. Typical uses include digital panel meters, digital voltmeters, laboratory instruments, temperature-measurement panels, process-monitoring displays, and weighing equipment. The ICL7135CPI+ is especially appropriate when a readable decimal display, differential input, and deterministic integration cycle are more important than high conversion throughput. The BCD outputs are intended to interface naturally with digit drivers and display-oriented instrument designs. Designers should verify reference accuracy, input-common-mode range, integration-cycle timing, digit-driver polarity, and display multiplexing against the manufacturer datasheet before layout release. Because this is a through-hole 28-pin DIP device, its physical package differs from surface-mount display ADC families and should not be treated as a board-level equivalent. The manufacturer datasheet remains the controlling source for pin names, timing, and electrical limits. This page consolidates the verified distributor price, package information, function description, available drop-in candidates, comparison parameters, and practical design cautions. That engineering-focused context helps buyers distinguish a genuine 28-pin replacement from a merely similar 4.5-digit converter and supports faster qualification without replacing the manufacturer datasheet as the authoritative design reference.
ICL7135CQI+ - 4.5-Digit Differential ADC | Analog Devices
The Analog Devices ICL7135CQI+ is a 4.5-digit monolithic analog-to-digital converter with differential inputs, multiplexed BCD outputs, and a 28-pin PLCC package. The device combines a 2.0000 V full-scale input capability with accuracy specified as ±1 count in 20,000 and is designed for precision measurement systems requiring direct BCD display output. A dual-slope ADC is a signal-conversion architecture that integrates an unknown input voltage over a defined interval and compares it with a reference-driven ramp. In a broader hierarchy, the ICL7135CQI+ is an ADC, a data-converter IC, and a precision measurement component. Its BCD outputs can reduce the display-processing burden in instruments, while differential input architecture helps reject common-mode disturbances when suitable source and reference arrangements are used. Key characteristics include 4.5-digit resolution, differential analog inputs, multiplexed parallel BCD outputs, and dual output polarity. The Analog Devices product page identifies the ICL7135 as a high-precision monolithic converter with ±1 count in 20,000 accuracy. These attributes make it applicable to laboratory instruments, panel meters, weighing systems, temperature measurement, and other linear analog measurement products. The converter architecture divides each measurement cycle into distinct phases controlled by internal counters, input interfaces, output interfaces, and control logic. Its differential input stage operates with high input impedance, which is useful when measuring slowly changing sensor signals and when the source impedance is not extremely low. The 2.0000 V full-scale reference requirement also places a clear constraint on analog front-end and reference design. Typical applications include digital panel meters, laboratory measurement equipment, process monitoring, resistance and temperature measurement, and other display-oriented instruments. The multiplexed BCD outputs are particularly useful when the measured value must be presented directly through seven-segment display drivers without requiring a complex digital data bus. For PCB implementation, place the input, reference, and bypass connections according to the manufacturer datasheet and keep sensitive analog routing compact. Designers should also verify timing, conversion-cycle behavior, display multiplexing requirements, and output logic levels against the target instrument rather than treating the converter as a generic modern high-speed ADC. This product page organizes the verified technical characteristics, sourcing information, drop-in candidate assessment, application guidance, and design considerations around the ICL7135CQI+. It is intended to help engineers determine whether its dual-slope architecture, BCD interface, differential inputs, and 28-pin PLCC package fit a precision display-oriented measurement design.
ICL7136CDL - 3.5-Digit LCD A/D Converter | Analog Devices
The Analog Devices ICL7136CDL is a low-power 3.5-digit analog-to-digital converter with integrated seven-segment decoders, display drivers, voltage reference, and clock circuitry in a 40-pin CERDIP package. It is designed for direct interface with a liquid-crystal display and supports measurements with very high input impedance, reducing the loading applied to the sensed signal. An integrated A/D converter is a mixed-signal IC that converts an analog input voltage into a digital numeric value. The ICL7136 belongs to the ADC/DAC category, combines data conversion with display-interface functions, and is used where a compact measurement system must present a value directly on an LCD. Unlike a discrete measurement design, it integrates the conversion, reference, clock, decoding, and display-driving blocks into one device. The converter provides 3.5-digit resolution, low-power operation, seven-segment display decoding, LCD segment drivers, a multiplexed LCD backplane output, an internal voltage reference, and an integrated clock. Overrange recovery is an improvement over the earlier ICL7126. The available product listing identifies the ICL7136CDL specifically as a 40-CERDIP device, making it suitable for established through-hole industrial, laboratory, and instrumentation designs. Internally, the device combines successive-approximation conversion techniques with the supporting analog and digital blocks needed for autonomous panel measurement. The integrated reference reduces the number of precision external components, while the high-impedance input helps preserve the accuracy of the signal under test. The segment decoders and LCD drivers reduce display-interface complexity compared with a general-purpose converter followed by a separate display controller. Typical applications include digital panel meters, laboratory measurement instruments, temperature measurement systems, process-monitoring equipment, weighing indicators, and portable diagnostic instruments. In each case, the converter can drive the LCD directly while the external analog front end determines the measured quantity. The LCD architecture also suits handheld or bench instruments where a numerical display is more practical than a host-controlled graphical interface. Designers should verify the complete electrical limits, reference accuracy, conversion timing, input ranges, and display compatibility against the manufacturer datasheet before release. PCB layout must preserve the pinout of the 40-pin CERDIP footprint, provide adequate bypass capacitance, and keep sensitive analog-input routing away from display-driver and clock signals. External component values and timing requirements should not be inferred from generic ADC designs. This page combines verified manufacturer and distributor information, structured specifications, application guidance, sourcing questions, and explicitly recorded data gaps. It does not present unsupported electrical values as facts; unavailable parameters remain clearly identified in the specification table for engineering review.
ICL7136CMH - Low-Power 3.5-Digit ADC | Analog Devices
The Analog Devices ICL7136CMH is a low-power, 3.5-digit dual-slope analog-to-digital converter with automatic calibration, true differential input, and differential reference capability in a 44-pin MQFP package measuring 10 mm by 10 mm. Its primary specifications include a 3.5-digit resolution, 9 V operating supply, and 500 mW power dissipation rating. An ADC is a semiconductor that converts an analog voltage into a numeric value. The ICL7136 belongs to the dual-slope ADC family, a class of converters that integrates an input signal over a fixed interval and measures the resulting integration time against a reference. This technique is well suited to instruments where predictable behavior, rejection of periodic interference, and usable resolution matter more than very high conversion speed. Key features include automatic calibration, true differential input, and a differential reference arrangement. Automatic calibration helps establish a repeatable measurement baseline, while the dual-slope architecture rejects interference signals common in industrial environments. Differential measurements also support ratiometric sensing, where output code depends on the ratio of an unknown input to a related reference. The ICL7136 integrates a 3.5-digit BCD-to-seven-segment display driver, allowing measured values to be presented directly on common digital display devices. This combination of measurement and display excitation simplifies panel-meter, laboratory-instrument, and industrial-control designs by reducing the number of external interface components. Typical uses include digital panel meters, temperature measurement systems, resistive and bridge transducers, laboratory meters, and process-monitoring equipment. The differential input and reference architecture is particularly useful in ratiometric measurements, where sensing-element drift can be reduced when the excitation and measurement paths share corresponding variations. When designing around the ICL7136CMH, preserve the analog and reference layout implied by the manufacturer application guidance, use suitable input and reference filtering, and verify display-drive compatibility with the selected seven-segment display. Because the MQFP-44 package has fine-pitch leads and a thermal pad, assembly and layout planning should account for lead geometry, soldering process, and thermal dissipation. This product page consolidates the confirmed ICL7136 family characteristics, sourcing information, same-package alternatives, and practical selection guidance. It helps engineers compare the commercial-grade ICL7136 variants by package, temperature range, supply voltage, and power rating before committing to a PCB footprint.
ICL7136CPL+ - 3.5-Digit LCD A/D Converter | Analog Devices
Analog Devices ICL7136CPL+ is a low-power, 3.5-digit monolithic analog-to-digital converter with integrated seven-segment decoders, display drivers, voltage reference, and clock circuitry. The device is designed to interface directly with a non-multiplexed liquid-crystal display and includes a 40-pin PDIP package. Its headline specifications are 3.5-digit resolution, differential and single-ended input operation, and low-power conversion in a display-oriented integrated circuit. An integrated 3.5-digit A/D converter combines analog measurement, digital conversion, and display excitation in one package. This type of converter is used where a compact instrument must display a measured voltage, current, resistance, or temperature without requiring a separate display driver. The ICL7136CPL+ uses a dual-slope conversion technique, providing a measurement architecture suited to stable, low-rate instrumentation rather than high-speed signal acquisition. The ICL7136CPL+ includes onboard segment drivers, segment decoders, a voltage reference, and a clock, reducing the number of external display-support components required. The Analog Devices product page identifies it as a production part and describes it as a low-power 3 1/2-digit A/D converter. The integrated display interface is intended for LCD displays, while the converter's differential-input capability supports measurement arrangements that reject common-mode effects when used with suitable input circuitry. The dual-slope conversion method integrates the input over a fixed interval, providing a measurement result that is less sensitive to certain noise and timing variations than a simple instantaneous conversion. The device is intended for panel meters, digital instruments, laboratory measurement equipment, and other systems where a stable numeric display is required. External passive components and the selected input network remain important for achieving the intended accuracy and input impedance. Typical uses include handheld meters, process-monitoring displays, temperature-measurement instruments, laboratory equipment, and embedded display panels. In each case, the ICL7136CPL+ can combine the measurement front end and LCD drive functions while leaving the host system free to focus on control, data logging, or user interaction. Designers should follow the manufacturer pin-description table when assigning PCB nets and should confirm the display polarity, segment count, input configuration, reference arrangement, and bypass requirements against the manufacturer datasheet. The 40-pin PDIP footprint is mechanically straightforward but occupies substantial board area, so DIP availability and assembly method should be checked during product planning. This product page consolidates the ICL7136 family specifications, verified package information, sourcing guidance, comparison parameters, and practical replacement considerations to support faster engineering evaluation and board-level planning.
ICL7136CQH+ - Low-Power 3.5-Digit LCD A/D Converter | Analog Devices
Analog Devices ICL7136CQH+ is a low-power, 3.5-digit monolithic analog-to-digital converter with integrated LCD display-driver circuitry. The device is designed for measurement systems that require a high-input-impedance front end and direct excitation of a non-multiplexed liquid-crystal display. Its integrated block includes segment drivers, segment decoders, a voltage reference, and a clock circuit, reducing the need for external display-drive circuitry in suitable instrument designs. The ICL7136CQH+ is associated with the Maxim Integrated ICL7136 family and is offered in a 44-lead PLCC, or 44-LCC J-lead, package. A 3.5-digit A/D converter is commonly used for panel meters, laboratory instruments, process monitoring, weighing equipment, and portable measurement equipment. The 3.5-digit format provides adequate resolution for displaying a signed or unsigned measurement while maintaining a compact instrument layout. Because the ICL7136 integrates the display interface, the converter can be paired directly with a compatible non-multiplexed LCD when the display and board requirements match the device's electrical and timing specifications. The ICL7136 architecture is based on a dual-slope conversion approach, a technique commonly used in precision panel-meter converters because it provides good rejection of periodic noise when the integration and reference relationships are designed appropriately. The high input impedance helps isolate the measurement node from the converter input, allowing the sensor or signal-conditioning network to be designed around the required source impedance and measurement range. The integrated voltage reference and clock support a self-contained measurement channel, while the LCD outputs reduce the number of external display-driver connections. The ICL7136CQH+ is particularly relevant to industrial and laboratory instrumentation where a dedicated numeric LCD readout is preferred over a high-speed sampled data converter. The package and function make it suitable for panel-meter products, handheld test equipment, digital laboratory instruments, process indicators, and data-acquisition front ends with relatively slow measurement requirements. When evaluating the device, check the electrical limits, input configuration, reference requirements, display timing, and pin-specific connection requirements in the manufacturer data sheet. The 44-lead PLCC package is a through-hole, leaded surface-mount-style package with J-leads, making it different from small-outline and fine-pitch packages used in newer compact instruments. The principal design trade-off is integration and display convenience versus package size and the need to design around the converter's specified operating conditions. For new designs, confirm the exact package variant, temperature range, supply requirements, and pin assignment against the current Analog Devices or Maxim Integrated documentation.
ICL7137CDL - Dual-Slope 4.5-Digit ADC | Analog Devices
Analog Devices ICL7137CDL is a monolithic 4.5-digit dual-slope analog-to-digital converter designed to drive a light-emitting diode display directly. It operates from a bipolar power supply, supports automatic calibration, and draws less than 200 uA of supply current when LED display current is excluded. The converter is packaged in a commercial-grade, 40-pin through-hole DIP. The ICL7137CDL combines an analog input stage, dual-slope conversion system, digital counter, and display-driving circuitry in one integrated circuit. A dual-slope ADC is a type of integrating analog-to-digital converter that measures an unknown input voltage by integrating it for a fixed interval and then measuring the time required to return the integrator to zero. This technique provides good noise immunity for slowly changing signals, including outputs from temperature sensors, pressure transducers, strain gauges, and slow analog measurement systems. The ICL7137 family also incorporates auto-zeroing and auto-calibration functions intended to reduce offset and gain-related errors. The principal operating characteristics include a commercial temperature range of 0 C to +70 C, bipolar supply operation, automatic calibration, and supply current below 200 uA excluding display current. The low power consumption makes the converter suitable for battery-operated instruments and portable measurement equipment. The direct LED-display interface reduces the need for external display drivers, while the 40-pin DIP package supports conventional through-hole PCB assembly and prototyping. ICL7137CDL is most appropriate for precision digital voltmeters, panel meters, laboratory measurement equipment, temperature controllers, load-cell instrumentation, and general-purpose slow-rate data acquisition. When designing around the converter, the input signal range, reference voltage, integration period, system resolution, and display driver requirements must be evaluated together. A stable reference and carefully routed analog inputs are important because both directly influence conversion accuracy and repeatability. Thermal and supply design should account for the component's bipolar supply arrangement and the power contribution from the display. The datasheet should be consulted for the complete electrical limits, recommended operating conditions, input and reference topology, timing relationships, and pin descriptions before laying out a new board. Commercial temperature grade makes this suffix appropriate for indoor laboratory and industrial equipment where the specified ambient range is respected. This page consolidates the verified product characteristics, comparison limits, application guidance, and replacement considerations. It also identifies unresolved technical fields explicitly so engineers can distinguish documented operating facts from parameters that must be confirmed in the manufacturer datasheet before production release.
ICL7137CMH - 3.5-Digit LED ADC | Maxim Integrated
The Maxim Integrated ICL7137CMH is a monolithic 3.5-digit dual-slope analog-to-digital converter with active devices that directly interface with an LED display. The converter is packaged in a 44-pin MQFP measuring 10 x 10 mm and is identified as a one-channel ADC for LED display instrumentation. According to the Analog Devices product page, the ICL7137 consumes less than 200 uA, excluding the current required by the LED display, making it suitable for battery-operated instruments. An integrated 3.5-digit LED display ADC is a specialized data-converter and display-control component. It combines analog measurement, digital counting, and display drive functions in one monolithic device. The dual-slope conversion technique used by the ICL7137 integrates the input voltage over a fixed interval, rejecting periodic noise and providing accurate results for slow-moving or repetitive measurements. This architecture fits the hierarchy ADC > data converter > integrated circuit > semiconductor. The defining feature of the ICL7137 is direct LED-display support. Unlike a general-purpose ADC that outputs only a digital code, the device includes the active circuitry needed to illuminate a multiplexed seven-segment display. The 3.5-digit format supports readings from negative 999 through positive 999, subject to the detailed reference, input, and operating conditions in the manufacturer datasheet. Its low supply current makes it especially relevant to handheld meters, panel instruments, and portable measurement systems. Dual-slope conversion offers useful advantages for panel meters because its accuracy does not depend on a high-frequency clock being multiplied into the measurement result in the same way as many successive-approximation converters. The averaging behavior helps attenuate periodic interference. The manufacturer describes versatility and accuracy as inherent features of the converter, while the integrated clock, reference, counter, and display-driver functions reduce the external component count required for a complete measurement instrument. Typical implementations include digital multimeters, laboratory panel meters, temperature-measurement instruments, process-monitoring displays, laboratory equipment, and battery-powered meters. The direct LED interface is especially valuable when a readable numerical display is required at the point of measurement. Such systems can use the converter without adding a separate display decoder or segment driver, reducing board area and simplifying firmware requirements. The main design considerations are reference stability, input-range implementation, display current, layout, and timing. The input and reference networks must be designed around the electrical limits specified by the manufacturer datasheet. Display resistors and LED current determine brightness and power consumption, while the under-200-uA supply-current figure explicitly excludes display current. PCB placement should keep analog input, reference, and clock paths away from display-return currents and switching nodes. This page organizes the ICL7137CMH specifications, package information, sourcing path, practical use cases, and verified same-footprint alternatives. It also separates the low converter supply consumption from the additional power demanded by the LED display, helping engineers evaluate both instrument accuracy and battery-life requirements before selecting the ADC and display circuitry.