ICL7109EQH - 12-Bit Dual-Slope ADC | Analog Devices
MPN： ICL7109EQH ✓ 啟用中ICL7109EQH 概覽
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.
直接替換替代品，適用於 ICL7109EQH — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
ICL7109EQH+D
✅ 直接替換📋 參考替代品（不在目錄中）
ICL7109CQH+TD
✅ 直接替換📋 參考替代品（不在目錄中）
ICL7109CPL+
✅ 直接替換📋 參考替代品（不在目錄中）
ICL7109EQH 最大額定值與電氣特性
| Converter Type | Dual-slope ADC |
| 解析度 | 12 bit |
| Input Channels | 1 channel |
| 輸出類型 | 3-state binary output |
| Output Data Format | Binary with polarity and over-range outputs |
| 封裝 | 44-PLCC (16.59 mm x 16.59 mm) |
| 安裝類型 | Surface mount |
| 工作溫度 | 0 C to +70 C |
| Input Type | Bipolar |
| Supply Type | Bipolar power supply |
| Power-On Reset | Present |
| Processor Interface | Microprocessor bus with chip select and two byte-enable inputs |
ICL7109EQH 44-plcc (16.59 mm x 16.59 mm) 腳位配置指南
ICL7109EQH（44-plcc (16.59 mm x 16.59 mm) 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： ICL7109EQH.
請參閱 資料表 以查看完整腳位配置。
典型應用
ICL7109EQH 適用於 6 應用s: Digital Panel Meters, Temperature Measurement, Process Monitoring, Laboratory Instrumentation, Remote Data Logging, Precision Measurement Systems.
Digital Panel Meters
The ICL7109EQH fits slow digital panel-meter designs that require a stable numeric reading rather than rapid waveform acquisition. Its 12-bit dual-slope conversion provides 4096 numerical codes, while the binary, polarity, and over-range outputs allow the controller to display both the measured value and basic status. The 44-PLCC footprint favors through-board assembly and socketed service access. Designers should use the manufacturer timing and input-filtering guidance, then verify that the measurement update rate is acceptable for the displayed quantity.
推薦
Temperature Measurement
The ICL7109EQH is suitable for periodic temperature measurement with resistive sensors, thermocouples, or conditioning circuits whose signals change slowly relative to the conversion interval. A 12-bit result offers useful display resolution, and the polarity output can support bipolar sensor conditions. Accuracy still depends on the sensor, reference source, analog front end, cold-junction compensation where applicable, and input filtering. Confirm the exact input range and timing limits from the manufacturer data sheet before defining the measurement resolution.
推薦
Process Monitoring
The ICL7109EQH can serve as the measurement engine in industrial process-monitoring equipment that samples pressure, level, flow, or other slowly varying analog quantities. Dual-slope operation is well matched to instrumentation in which reference accuracy and repeatable readings matter more than high conversion frequency. The controller can retrieve the 12-bit binary value and use the polarity and over-range outputs to flag invalid or exceptional conditions. Sensor excitation, isolation, surge protection, and calibration strategy remain important system-level requirements.
推薦
Laboratory Instrumentation
The ICL7109EQH is appropriate for bench instruments and laboratory measurement systems that require a readable, repeatable result from a slowly changing analog input. The three-state binary outputs simplify bus sharing when multiple converter channels are present, while chip select and two byte-enable inputs support microprocessor control. Instrument designers should give special attention to reference-voltage stability, input leakage effects, grounding, and calibration because these factors often determine whether the converter's nominal resolution is realized in the finished system.
推薦
Remote Data Logging
The ICL7109EQH is suitable for remote data-logging equipment in which a host processor periodically acquires a sensor value and stores or transmits it. Its three-state outputs help multiple converters share a bus, and the polarity plus over-range indicators allow the host to reject or flag exceptional readings. In field deployments, protect the analog input and reference path from transients, provide appropriate filtering, and account for temperature drift. Firmware should also detect missing or invalid conversions before treating the numerical output as a valid measurement.
推薦
Precision Measurement Systems
The ICL7109EQH fits precision measurement systems that convert low-speed analog quantities into digital readings for recording or control. Its 12-bit dual-slope architecture provides 4096 numerical codes, while the over-range output gives the host a direct indication of an input outside the usable measurement region. To maximize practical accuracy, follow the manufacturer recommendations for reference components and input filtering, keep sensitive traces away from switching nodes, and validate the complete signal chain with calibrated inputs rather than inferring accuracy from the converter's bit count alone.
推薦
推薦產品摘要
工程參考資料，適用於 ICL7109EQH — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ICL7109EQH+D | ICL7109CQH+TD | ICL7109CPL+ |
|---|---|---|---|---|
| Package | 44-PLCC (16.59 mm x 16.59 mm) | 44-PLCC (16.59 mm x 16.59 mm) | 44-PLCC | PLCC-44 |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit |
| Conversion Architecture | Dual slope | Dual-slope | Dual-slope | Dual slope |
| Input Channels | 1 channel | 1 channel | 1 channel | 1 channel |
主要差異化特點
- Direct three-state binary interface for bus-oriented measurement systems (對比ICL7109CPL+)
- Exact-family ordering option with unchanged converter core (對比ICL7109EQH+D)
- PLCC-44 construction supports established leaded assembly processes (對比ICL7109CQH+TD)
設計說明
Use the manufacturer PLCC-44 land pattern and verify it against the physical 16.59 mm by 16.59 mm package. Confirm the pin-1 orientation, lead pitch, solderable area, and assembly clearance before releasing the layout. Because the converter includes sensitive analog inputs and a reference path, route those nets away from switching nodes and maintain a quiet return path beneath or adjacent to the analog section where the board stack-up permits.
Follow the manufacturer guidance for input filtering, reference bypass, and grounding. External filtering helps reject high-frequency noise that could otherwise influence the integrated measurement, while a stable reference is essential to dual-slope accuracy. Validate the complete analog path with known input levels and check polarity and over-range behavior at both operating extremes rather than relying only on the nominal 12-bit conversion code.
Do not treat the base part number as a complete orderable configuration. ICL7109EQH, ICL7109EQH+D, ICL7109CQH+TD, and ICL7109CPL+ can differ in ordering code, temperature grade, reference implementation, qualification, or packing. Compare the exact manufacturer ordering table, pin descriptions, reference requirements, and timing limits before replacing an installed device or approving a new assembly.
Allow adequate assembly access for the leaded PLCC package and account for socket height, component spacing, and lead-forming requirements. Unlike a leadless fine-pitch package, a PLCC footprint can introduce lead-pitch and soldering-process considerations that affect inspection and rework. Prototype the footprint with representative components when the assembly house has limited experience with 44-pin PLCC packages.
合規資訊
The ICL7109 is an industrial/consumer mixed-signal converter rather than an automotive-qualified device. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status require confirmation from the current manufacturer product documentation or declaration for the exact ordering suffix.
