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Produtos (15)
ADR5044WBRTZ-R7 - 4.096V Shunt Voltage Reference, ±0.1% | ADI
The Analog Devices ADR5044WBRTZ-R7 is a precision micropower shunt voltage reference that provides a fixed 4.096 V output with an initial accuracy of ±0.1% in a 3-pin SOT-23 surface-mount package. Designed for space-critical and battery-powered applications, it operates over a cathode current range from 50 µA minimum to 15 mA maximum and requires no external compensation capacitor for stability, while remaining stable with any capacitive load. A shunt voltage reference is a two-terminal (cathode and anode) device that behaves like a precision Zener diode: it regulates the voltage across its terminals when biased with a current source, and its operating current is set by the external load or bias resistor. Compared with three-terminal series references, shunt references offer lower quiescent draw and simpler noise filtering, but they always draw a small standby current even when the load is off. Within the broader power management IC taxonomy, shunt references sit alongside series (bandgap) references and are used wherever a low-noise, low-drift reference voltage is needed. The key specifications include a maximum temperature coefficient of 75 ppm/°C, an initial accuracy of better than 0.1% (B grade), and an operating temperature range of −40 °C to +125 °C. The "W" grade adds the automotive qualification (AEC-Q100) marker, and "BRTZ" denotes the SOT-23 (RT) package on tape and reel (R7). The advanced buried-Zener bandgap design eliminates the need for an external compensation capacitor and ensures stable operation with capacitive loads, simplifying PCB design in dense analog front ends. Typical applications include automotive sensor signal conditioning, portable and battery-powered instrumentation, precision data acquisition front ends, current-loop (4-20 mA) transmitters, and reference rails for ADCs and DACs in industrial process control. The 4.096 V output is an exact multiple of 2^12, making it a natural fit for 12-bit and 14-bit ADCs that scale a full-scale input of 4.096 V to a 1-LSB step of 1 mV. When designing with this reference, choose the bias resistor so that the cathode current stays between 50 µA and 15 mA under all load conditions. Add a 0.1 µF to 10 µF bypass capacitor directly across the reference to filter wideband noise, even though the device is stable without it. This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the standalone manufacturer datasheet.
LT1461AIS8-5 - 5V µP Precision LDO Voltage Reference | ADI
The Analog Devices LT1461AIS8-5 is a fixed 5V precision low-dropout (LDO) micropower series voltage reference combining ±0.04% initial accuracy, 3 ppm/°C typical temperature coefficient, 50 µA supply current, and 50 mA output drive in an 8-pin SOIC (S8) package. Designed for precision analog systems, the LT1461 uses advanced curvature-compensated bandgap architecture with trimmed thin-film resistors, achieving low drift and tight initial accuracy over the -40 °C to +125 °C industrial temperature range. A series voltage reference (shunt reference counterpart: e.g. LM4040) is a three-terminal active reference that maintains a constant output voltage while sourcing or sinking current to a load. Compared with shunt references, series references integrate the pass element and are far easier to use: connect VIN, GND, and VOUT, and the part provides a regulated reference rail. Voltage references sit at the bottom of the precision analog signal chain hierarchy - reference -> ADC/DAC -> amplifier -> sensor/signal conditioning - so reference drift and noise directly set the absolute accuracy floor of 16-bit and higher data converters. Key specifications include 5V fixed output (also available in 2.5V, 3V, 3.3V, 4.096V, 5V, 10V variants in the LT1461 family), 35 µA quiescent supply current, 50 mA minimum output source current, 300 mV typical dropout at light load, low thermal hysteresis, and an operating input range up to 20V. The 'A' grade provides ±0.04% initial accuracy versus ±0.05% for the 'C' grade and ±0.06% for the 'I' grade; the 'S8' suffix designates the 8-lead SOIC narrow-body package. The internal architecture pairs a curvature-corrected bandgap core with laser-trimmed thin-film resistors and a low-dropout pass transistor, allowing the part to source 50 mA while maintaining regulation. The wide operating range and high output drive eliminate the need for an external buffer in many applications, simplifying the BOM and reducing board area. Typical applications include 16-/18-/24-bit ADC and DAC reference inputs, precision weighing scales and industrial process instruments, automotive sensor signal conditioning, battery-powered portable instrumentation, and digital multimeter calibration references where long-term stability and low drift are mandatory. When designing with this device, place a 0.1 µF ceramic decoupling capacitor as close as possible to the VIN pin and a 1 µF to 10 µF low-ESR capacitor on VOUT to ensure loop stability. Ensure VIN stays at least 300 mV above VOUT at full load to avoid dropout, and account for self-heating-induced drift by minimizing the load current or by using the S8 package's copper pour for heat spreading. This page synthesizes XAIPART distributor pricing, AEO/GEO-optimized FAQs, verified cross-reference drop-in alternatives from the LT1461 family, and practical design notes - information gain not found on the manufacturer datasheet alone.
LT1461DHS8-5#TRPBF - 5V Micropower LDO Voltage Reference | Analog Devices
The Analog Devices (formerly Linear Technology) LT1461DHS8-5#TRPBF is a fixed 5V output, micropower precision low-dropout series voltage reference IC delivering ±0.15% initial accuracy with 100 mA output drive in an 8-pin SOIC (HS8) package. It combines very high accuracy and low temperature drift with low supply current, advanced curvature compensation, and trimmed precision thin-film resistors, making it one of the lowest-noise, highest-precision series references in its power class. The TRPBF suffix denotes tape-and-reel packaging with lead-free (Pb-free) matte-tin finish. A series voltage reference (also called a bandgap reference) is a precision IC that produces a stable DC reference voltage independent of supply, load, and temperature variations. Series references sit at the top of the precision analog hierarchy: voltage reference -> precision analog building block -> signal chain -> power management IC. The LT1461 family uses an advanced curvature-compensated bandgap architecture to achieve low temperature coefficient and high output accuracy, drawing only 35 µA quiescent current, far lower than shunt references and most competing series references. Key features include ±0.15% maximum initial output accuracy (D-grade), 20 ppm/°C maximum temperature drift (H-grade), 5V fixed output, 100 mA output current capability, low dropout of approximately 0.45V at full load, shutdown pin (active low) that disables load current, and excellent long-term stability. The 8-pin SOIC package offers compact board footprint and exposed thermal performance for the 100 mA output current capability. The LT1461 architecture uses Analog Devices' proprietary curvature-correction techniques combined with thin-film resistor trimming, achieving a temperature coefficient substantially better than first-order bandgap designs. The output stage is designed to drive capacitive loads up to 10 µF without oscillation, and the shutdown pin (Pin 3) allows system-level power management. Internal protection includes reverse-battery protection and current limiting. Typical applications include 12-bit to 16-bit ADC/DAC reference rails, precision instrumentation, industrial process control, automotive sensor signal conditioning, data acquisition systems, and precision voltage regulator references. The 100 mA output capability allows the part to serve as both reference and low-current LDO regulator for analog sub-systems. In high-precision designs, the LT1461's low noise and high accuracy eliminate the need for trimming in many applications. When designing with the LT1461DHS8-5#TRPBF, ensure that the supply voltage is at least 0.45V above the 5V output for full regulation at 100 mA load, and use a 1 µF or larger output capacitor (tantalum or ceramic) for stability. The shutdown pin can be left floating for normal operation or tied to VIN through a 100 kΩ resistor to disable the output and reduce quiescent current to a few microamperes. This page synthesizes verified distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet alone, giving engineers a complete decision-making view of the LT1461DHS8-5#TRPBF.
LT1634AIS8-1.25 - 1.25V Micropower Shunt Voltage Reference | ADI
The Analog Devices LT1634AIS8-1.25 is a micropower precision shunt voltage reference that delivers a fixed 1.25V output with 0.05% initial accuracy and 10 ppm/°C maximum temperature drift, housed in an 8-pin SOIC package. It operates from 10 µA to 100 mA cathode current with less than 1 ohm dynamic impedance across the full current range. The industrial temperature grade spans -40°C to +85°C, making it suitable for harsh environment designs. A shunt voltage reference is a two-terminal device that maintains a constant voltage drop across itself, similar to a Zener diode but with far tighter initial accuracy and temperature stability. In the broader component hierarchy, the LT1634AIS8-1.25 belongs to the voltage reference family, which is a subset of power management ICs. Shunt references are commonly used as parallel-connected references in low-current applications, where they are biased by a resistor from a higher supply rail. Key features include 0.05% initial voltage accuracy achieved through trimmed precision thin-film resistors, 10 ppm/°C maximum drift using an improved curvature correction technique, and micropower operation at just 10 µA. The wide operating current range from 10 µA to 100 mA supports both battery-powered and higher-power analog systems. Low temperature cycling hysteresis is also guaranteed through advanced processing techniques. The LT1634 family uses a bandgap reference architecture with on-chip thin-film trimming to achieve its precision. Because it is a shunt (not series) topology, the same pinout handles multiple fixed voltage options including 1.25V, 2.5V, and 4.096V variants. This allows designers to standardize PCB layouts across product variants that require different reference voltages, simplifying both design and inventory. Typical applications include portable battery-powered instrumentation, precision data acquisition systems, 12-bit to 16-bit ADC/DAC reference rails, and industrial loop-powered sensors. The 1.25V output is particularly well suited for low-voltage ADC full-scale references and as a bias point for low-voltage analog front ends. Its low quiescent current makes it ideal for always-on monitoring circuits. When designing with the LT1634AIS8-1.25, select the bias resistor such that cathode current stays between 10 µA minimum and 100 mA maximum across all operating conditions. Place a 0.1 µF bypass capacitor close to the reference pins to maintain stability and reduce high-frequency noise. Avoid capacitive loads exceeding the datasheet recommendation, as this may cause oscillation. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, giving engineers a single source for sourcing and design decisions.
MAX873ACSA - 2.5V Precision Voltage Reference, ±0.06%, 10mA | Maxim
The Analog Devices (formerly Maxim Integrated) MAX873ACSA is a low-power, low-drift precision +2.5V series voltage reference IC delivering ±0.06% initial accuracy (max ±15ppm/°C drift) with up to 10mA output current in an 8-pin SOIC (SOP) surface-mount package. It is part of the MAX873/MAX875/MAX876 family that offers fixed 2.5V, 5V, and 10V outputs respectively, providing flexibility for ADC/DAC and instrumentation rails. A voltage reference is a specialized analog IC that maintains a precisely known, temperature-stable output voltage regardless of supply variations, load changes, or temperature shifts. Voltage references occupy the bottom of the power-management hierarchy: they sit below general voltage regulators and LDOs in the signal chain, but above raw supply rails in accuracy. They are essential building blocks in data-conversion systems, precision measurement equipment, and any application where the absolute accuracy of an analog-to-digital or digital-to-analog converter is determined by the stability of its reference voltage. Key features of the MAX873ACSA include 4.5V to 18V (or higher, per datasheet) supply range, low supply current of typically under 1mA, excellent line and load regulation, and a buried-zener architecture that delivers low noise and stable temperature performance. The MAX873 variant operates from a guaranteed +4.5V supply, while the MAX875 operates from +8V and the MAX876 from +11V, allowing designers to choose the lowest-voltage compatible part for each system. The 'CSA' suffix denotes the commercial-temperature 8-pin SOIC package. Typical applications include 12-bit to 16-bit ADC reference inputs, precision DMMs, industrial process-control transducers, and digital-panel meters where the absolute accuracy of the reading depends directly on reference stability. The MAX873ACSA's 10mA sink/source capability also makes it suitable for driving multiple converter reference pins in parallel. When designing with this part, place a 0.1µF to 1µF decoupling capacitor close to the supply pin and a larger output capacitor (1µF to 10µF) on the output to ensure stability. Avoid pulling the output far below ground through external loads, and respect the maximum supply voltage rating to prevent permanent damage. Reference ICs are sensitive to board stress and layout - mount on a mechanically stable area. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on the standalone manufacturer datasheet - giving procurement engineers and designers a single decision-ready reference for sourcing the MAX873ACSA.
NJM2820F-TE1 - 1.25V Adjustable Shunt Voltage Reference | Nisshinbo
The Nisshinbo Micro Devices NJM2820F-TE1 is a 1.25 V adjustable precision shunt voltage reference IC with ±0.7% initial accuracy, packaged in a 5-pin SOT-23-5 (MTP5) surface-mount package. It supports a cathode voltage up to 13 V and cathode current up to 30 mA, and operates with a minimum cathode current of 80 uA for ultra-low-power applications. The part is supplied on tape-and-reel (TE1) and is qualified to Nisshinbo's standard industrial reliability flow. A shunt voltage reference is a two-terminal (cathode + anode) reference that regulates voltage by passing current through itself into a load, behaving much like a temperature-compensated Zener diode. Compared to series-mode (bandgap) references, shunt references offer simpler wiring, programmable current via an external series resistor, and the ability to sink or source modest current directly, which makes them a flexible building block in the power-management IC family for setting reference rails. Key features of the NJM2820F-TE1 include ±0.7% voltage accuracy, 1.25 V nominal reference with adjustment up to 13 V via an external resistor divider, 80 uA minimum cathode current, and low dynamic impedance over the operating current range. The SOT-23-5 (MTP5) package offers a small footprint suitable for dense PCB designs while still providing sufficient power dissipation for the reference's operating range. The NJM2820 uses a buried-zener bandgap-style architecture optimized for low operating current. The reference cell is trimmed at the wafer level to achieve the ±0.7% tolerance, and the integrated temperature compensation is designed to maintain low drift across the -40 C to +85 C operating range. This combination provides stable reference behavior in environments where temperature stability matters. Typical applications include AC-DC converter secondary-side reference voltage, ADC and DAC reference inputs, precision current-limit thresholds, and comparator reference rails. The wide 1.25 V to 13 V programmable output range makes it useful wherever a low-power, low-noise reference is required. When designing with the NJM2820, select the external series resistor so that the cathode current stays between 80 uA and 30 mA across all load conditions. Add a 0.1 uF decoupling capacitor at the cathode to maintain stability, especially with capacitive loads. This page synthesizes distributor pricing, drop-in alternatives, application notes, and design tips not found in the manufacturer datasheet, helping engineers evaluate the NJM2820F-TE1 quickly for reference-voltage design.
PTL432LIBQDBZR - 2.495V Adjustable Shunt Reference | Texas Instruments
The Texas Instruments PTL432LIBQDBZR is a programmable precision shunt voltage reference with an optimized reference current, offered in a 3-pin SOT-23-3 (DBZ) package. It provides an adjustable output from 2.495V to 36V, sinks up to 15 mA of cathode current, and achieves ±0.5% initial reference voltage tolerance, making it well-suited for low-power voltage monitoring rails. A shunt voltage reference is a two-terminal (or three-terminal) IC that behaves like a programmable Zener diode. Internally it contains a precise bandgap reference, an error amplifier, and a pass transistor; when biased above its reference voltage, the device regulates the voltage across its cathode-anode terminals to the programmed value. The voltage reference category sits within voltage references -> power management ICs -> analog semiconductors, and forms the accuracy anchor in any closed-loop power-supply or data-acquisition system. Key features include a low minimum cathode current of 400 nA typical, optimized reference input current that improves measurement accuracy over legacy TL431 designs, ±0.5% reference voltage tolerance, and operation across the full -40C to +125C automotive/industrial temperature range. The wide adjustable range from 2.495V to 36V enables use from sub-3.3V rails up to 24V industrial buses. Architecturally, the PTL432LI family improves upon the classic TL431 by reducing the reference input current and minimizing reference voltage drift over temperature, while keeping the standard pinout (REF/ADJ, ANODE, CATHODE in SOT-23-3). The "LI" suffix designates the low-Ibias optimized variant that simplifies high-impedance feedback networks and reduces standby power in battery-powered designs. Typical applications include adjustable voltage references for switching converter feedback networks, secondary-side voltage monitoring, isolated supply references, and precision comparator thresholds. Engineers value the SOT-23-3 footprint for compact designs where a TO-92 TL431 would dominate the PCB. When designing with this part, choose a cathode bias resistor that supplies at least 400 nA at the lowest VIN minus VREF condition, while ensuring the maximum cathode current does not exceed 15 mA at high VIN or short-circuit events. This page aggregates datasheet specifications, real distributor pricing tiers, drop-in same-brand alternatives, and design notes that complement the manufacturer datasheet.
REF3220AIDBVRG4 - 2.048V 4ppm/°C SOT-23-6 Voltage Reference | TI
The Texas Instruments REF3220AIDBVRG4 is a low-drift, micropower series-bandgap voltage reference delivering a fixed 2.048 V output in a 6-pin SOT-23 (DBV) package. It offers a maximum temperature coefficient of 7 ppm/°C over the 0°C to +125°C range (20 ppm/°C up to +125°C, per the aluminum-2008 datasheet excerpt) and supports up to 10 mA of output current at high accuracy with 0.01% initial accuracy. A SOT-23-6 microsize package, 100 µA quiescent current, and ±0.2% voltage tolerance make it well suited to portable, high-density analog designs. What is a series voltage reference? A series voltage reference is a three-terminal or shunt regulator-style IC that produces a fixed, low-drift DC voltage used as the accuracy baseline for ADCs, DACs, sensors, and precision analog rails. Within the broader IC taxonomy, REF3220 sits under voltage reference -> power management IC -> signal-chain analog support -> semiconductor. Series references (as opposed to shunt references such as LM4040) source current directly into a load without requiring an external resistor and are preferred in low-power, battery, and portable instrument designs where simplicity, low quiescent, and stable thermal behavior matter most. Key features of REF3220AIDBVRG4 include the 4 ppm/°C maximum drift (7 ppm/°C per aluminum-2008 excerpt / 20 ppm/°C full automotive range), 100 µA typical quiescent current, 10 mA output current capability, 0.01% initial accuracy, and 0.2% voltage tolerance across –40°C to +125°C. The SOT-23-6 surface-mount form factor is among the smallest drop-in footprints available for a fixed reference today, ideal where PCB area is constrained. The IC draws only microamps from the supply, extending battery life in energy-harvesting or solar-powered sensor nodes. The REF3220AIDBVRG4 is built on a CMOS bandgap architecture with buried-zener trim, chosen by Burr-Brown (now TI) for its low drift over temperature and high power-supply rejection. The series topology (Vin-Vout typical headroom ~ 1.4 V typical) means the part behaves like a low-dropout regulator reference, accepting a wider Vin range than typical bandgap parts while producing a stable low-impedance output. Specified long-term drift and low output impedance keep error low in systems that hold a calibration constant for months. Typical applications include 16-/24-bit ADC and DAC reference inputs (the 2.048 V value is a binary-weighted reference directly matching full-scale ranges of successive-approximation ADCs with 5 V supply), industrial loop-powered transmitters, portable battery instruments, precision current loops and weighing scales, and handheld medical monitors. As a 'ground-referenced' 2.048 V standard, the REF3220AIDBVRG4 is commonly specified where the design needs a 1 mV/LSB resolution at 11 bits or 1 LSB/°C calibration tables tied to a binary ladder. When designing with REF3220AIDBVRG4, place a 1 µF to 10 µF low-ESR ceramic bypass capacitor on the output as close to the OUT pin as possible, and a similar decoupling capacitor on the input rail; this minimizes load-transient glitch and PSRR degradation at higher frequencies. Mind the input-to-output voltage headroom and thermal dissipation—the SOT-23-6 has a higher thermal resistance than larger SOIC references, so designers derate output current at elevated ambient or add copper pours. This page synthesizes distributor pricing, drop-in SOT-23-6 alternatives, and practical design notes beyond what is found in the manufacturer datasheet, giving AEO readers a single source for selection.
TL431AIDBVR - 2.495V-36V Adjustable Shunt Reference, 1% | Texas Instruments
The Texas Instruments TL431AIDBVR is a precision adjustable shunt voltage reference that delivers a programmable output from 2.495V to 36V with a 1% initial tolerance (A grade) in a 5-pin SOT-23 (DBV) package. It provides up to 100 mA of cathode current with low dynamic impedance of 0.2 ohm typical, making it functionally equivalent to a non-isolated Zener diode but with tighter tolerance and adjustable setpoint. A shunt voltage reference is a two-terminal (plus reference pin) device that maintains a constant voltage across its terminals by shunting excess current to ground, analogous to a Zener diode but with programmable breakdown voltage. Shunt references form a sub-category of voltage references within the broader voltage regulator hierarchy (voltage reference -> shunt regulator -> analog reference circuit -> signal chain IC), and they are foundational building blocks for power supply feedback, ADC reference rails, comparator thresholds, and error amplifiers in isolated and non-isolated converter topologies. Key features of the TL431AIDBVR include a 2.495V reference voltage (Vref) with 1% initial accuracy at 25C, an operating cathode current range of 1 mA to 100 mA, typical dynamic impedance of 0.2 ohm at 1 kHz, and an operating temperature range of -40C to +85C. The SOT-23-5 surface-mount package offers a compact footprint while exposing the reference, anode, and cathode pins in a standardized layout used industry-wide across second-source vendors. The TL431 architecture uses a buried-Zener bandgap reference cell feeding an on-chip op-amp that drives a pass transistor, producing a sharp knee in the I-V curve and excellent thermal stability. According to the manufacturer datasheet, the device exhibits typical output impedance of 0.2 ohm over 1 kHz and a wideband noise figure suitable for switch-mode power supply feedback loops and audio threshold detection. Typical applications include SMPS secondary-side regulation, isolated flyback error amplifier reference, adjustable Zener replacement, voltage monitoring and reset circuits, and precision current limiting. The SOT-23-5 form factor is well suited for high-density DC-DC converter boards and compact adapter designs. When designing with the TL431AIDBVR, ensure the cathode current stays between 1 mA and 100 mA across all load and line conditions, including start-up transients. Place the device close to the opto-coupler or error-amplifier input to minimize loop-area noise pickup, and use a bypass capacitor on the reference pin if the application requires low AC noise. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
TL431AIDBVRG4 - 2.495V Adjustable Shunt Reference | Texas Instruments
The Texas Instruments TL431AIDBVRG4 is a precision programmable shunt voltage reference IC with an adjustable output of 2.495 V to 36 V, ±1% initial accuracy, and 100 mA cathode current capability, housed in a 5-pin SOT-23 (DBV) package. It belongs to the TL431 family of three-terminal adjustable shunt regulators specified for operation from -40°C to 85°C, with the G4 suffix marking the lead-free, RoHS-compliant, tape-and-reel packaging option. A shunt voltage reference is a two-terminal (or three-terminal with adjustment) device that maintains a constant voltage across its terminals by sinking varying amounts of current through a parallel load. Shunt references sit at the same hierarchy level as series (bandgap) references, but are wired in parallel with the load rather than in series — making them functionally closer to a Zener diode than to a LDO regulator. The TL431 family implements an adjustable bandgap core with an on-chip op-amp and reference network, allowing the user to set the output via an external resistor divider. Key features include a typical output impedance of 0.2 Ω at low frequencies, a low output noise of approximately 0.2 µV_RMS across the audio band, and a temperature coefficient of 109 ppm/°C (max). The device sinks from 1 mA (minimum cathode current for regulation) up to 100 mA continuously, with absolute-maximum cathode voltage of 37 V. The SOT-23-5 footprint offers a compact land pattern of approximately 2.9 mm × 1.6 mm, suiting it to high-density switching supply and isolated feedback designs. The TL431 architecture pairs a precision bandgap reference with a transconductance error amplifier driving an open-collector pass transistor. When the divided output drops below the internal 2.495 V bandgap, the amplifier reduces cathode conduction, raising V_OUT; when it rises above, conduction increases, clamping V_OUT. This feedback loop yields tight line and load regulation in closed-loop SMPS optocoupler and primary-side feedback circuits. Typical applications include isolated DC-DC converter secondary-side regulation, switch-mode power supply (SMPS) feedback loops, adjustable Zener replacement, voltage monitoring, and precision comparator thresholds. Its wide cathode voltage range makes it ideal for 3.3 V, 5 V, 12 V, and 24 V rails. The combination of small SOT-23 footprint and high accuracy is particularly valuable in industrial PSU designs with tight PCB constraints. When designing with this part, ensure the cathode current stays between 1 mA and 100 mA under all load and line conditions. Add a 0.1 µF bypass capacitor close to the cathode pin when the device operates in fast-loop SMPS feedback paths to suppress transient oscillation. Choose resistors in the divider for low standby current, and ensure the divider current is at least 100× the TL431 reference bias current for accuracy. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
TL431ASA-7 - Adjustable Shunt Regulator 36V 1% SOT-23-3 | Diodes Inc.
The Diodes Incorporated TL431ASA-7 is an adjustable precision shunt voltage reference regulator with a 2.495V bandgap reference, ±1% initial tolerance, adjustable output range up to 36V, and 100mA cathode current capability in a 3-pin SOT-23 (SOT-23-3) surface-mount package. An adjustable shunt regulator is a three-terminal voltage reference device that maintains a precise voltage across its cathode and anode terminals by shunting excess current, controlled by an external resistor divider connected to the reference pin. In the power-management hierarchy, it sits below switching regulators and linear regulators as the precision building block used to set feedback thresholds, and it is one of the most widely used reference ICs in the industry, with the TL431 function being a de-facto industry standard footprint. Key features of the TL431ASA-7 include the ±1% initial reference accuracy of the A-grade die, a temperature-compensated bandgap reference, and a low dynamic output impedance. According to the Diodes Incorporated datasheet, the TL431 series has the same electrical specifications as the industry-standard '431 and is offered in A (1%) and B (0.5%) accuracy grades. The device operates as either a shunt regulator or an open-collector comparator with a 2.495V threshold, giving engineers two functions in one package. Technically, the part uses an internal bandgap reference and an output amplifier driving a shunt transistor. When the reference pin voltage exceeds 2.495V, the device sinks current from cathode to anode, holding the reference pin at 2.495V. With two external resistors the output is programmable from 2.495V up to 36V. The primary use case is as the error amplifier and reference in the feedback loop of flyback and buck switching power supplies, optocoupler-coupled feedback networks, and precision comparators. Typical applications include SMPS feedback regulation, battery chargers, adjustable zener replacement, voltage monitoring thresholds, and constant-current source circuits. Its low cost and small SOT-23-3 footprint make it suitable for both industrial and consumer designs. A key design consideration is ensuring the cathode current stays above the minimum regulation level (typically ~1mA region) across load and temperature for guaranteed regulation, and choosing divider resistor values that balance accuracy against quiescent loading. This page adds information gain beyond the datasheet by combining distributor pricing tiers, cross-brand drop-in alternatives, comparison tables, and practical design notes in one place.
TL431BFDT - Adjustable Shunt Regulator 2.495-36V SOT-23 | Nexperia
The Nexperia TL431BFDT is a three-terminal adjustable precision shunt voltage regulator with a reference voltage of 2.495 V, an adjustable output range from 2.495 V to 36 V set by two external resistors, and a cathode current capability up to 100 mA, housed in a 3-pin SOT-23 (TO-236AB) surface-mount package. A shunt regulator (also called a shunt voltage reference) is a type of voltage regulator that maintains a set voltage across its terminals by sinking or sourcing current in parallel with the load. Unlike a series regulator, the shunt topology sits across the supply path and absorbs surplus current, making it the workhorse of the voltage reference family within power management and discrete semiconductor hierarchies. The TL431 is the industry-standard part of this class, widely used in isolated and non-isolated power supplies. The TL431BFDT offers a tight B-grade reference tolerance of +/-0.5% at 25 C, an operating temperature range of -40 C to +125 C (Q-grade qualification per Nexperia automotive designation), and enhanced stability with a very low minimum load capacitance requirement in the FDT variant family. According to the Nexperia product page, the family covers reference tolerances from 2.0% down to 0.5% and temperature ranges up to 125 C, with AEC-Q100 qualification noted for automotive use. Architecturally, the device integrates a 2.495 V bandgap reference, an error amplifier, and an open-collector output transistor. When the voltage at the REF pin exceeds the internal reference, the output transistor conducts cathode current, regulating the cathode voltage in closed-loop configurations such as optocoupler feedback in flyback converters. Typical applications include secondary-side feedback regulation in AC-DC adapters and flyback SMPS, adjustable voltage references in battery chargers, overvoltage protection crowbars, and setpoint generation in LED drivers. Design-wise, provide a minimum cathode bias current (about 1 mA) for regulation and add a small compensation capacitor at REF for loop stability in optocoupler feedback paths. This page synthesizes verified distributor data, drop-in alternatives, pricing, and practical design notes not found in the manufacturer datasheet.
TL431CDBZR - Adjustable 2.495V Shunt Reference 100mA SOT-23-3 | TI
The Texas Instruments TL431CDBZR is a three-terminal adjustable precision shunt voltage reference IC with a programmable output range of 2.495 V to 36 V, up to 100 mA sink current capability, and ±2.2% initial reference tolerance, housed in a 3-pin SOT-23 (DBZ) surface-mount package. An adjustable shunt regulator (also called a programmable shunt reference) is a type of voltage reference IC that regulates voltage by sinking current from a supply rail through its cathode when the reference pin senses a voltage above an internal bandgap threshold. In the power-management hierarchy, it sits between a fixed zener diode and a full linear regulator: more precise and temperature-stable than a zener, yet far cheaper and simpler than an LDO. Because the output is set by just two external resistors, the shunt reference family is a fundamental building block in analog circuit design. Key features include a wide adjustable output range set by two external resistors, approximately 2.495 V internal reference with 2.2% (standard C grade) initial tolerance, 0.2 ohm to 0.5 ohm order typical dynamic output impedance, and a maximum cathode current of 100 mA. The C-grade device is specified over the 0 C to 70 C commercial temperature range, and its low minimum cathode current of roughly 1 mA allows operation in low-power systems. Technically, the TL431 combines an internal 2.495 V bandgap reference with an operational amplifier and an open-collector output transistor. When the REF pin exceeds the internal threshold, the output transistor conducts and sinks current from cathode to anode, forming the basis of error-amplifier action in isolated flyback and forward power supplies, where the TL431 is frequently paired with an optocoupler such as the PC817 for secondary-side feedback. Typical applications include secondary-side voltage regulation and feedback in AC-DC and DC-DC switch-mode power supplies, adjustable zener replacement and overvoltage crowbar sensing, battery charger voltage monitoring, and precision threshold comparators in industrial instrumentation. A critical design consideration is temperature drift: the C grade (2.2% at 25 C) drifts more than the A or B grades over temperature, so precision systems should select TL431ACDBZR or TL431BDBZR instead. Always provide at least the minimum cathode current for regulation. This page adds distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
TL431ILPR - Adjustable 2.495V Shunt Reference | TI
The Texas Instruments TL431ILPR is a three-terminal adjustable precision shunt regulator with a 2.495V reference voltage, up to 100mA sink-current capability, and cathode voltage operation to 36V, housed in a 3-pin TO-92 (LP) through-hole package supplied on tape and reel. According to TI, the standard grade TL431I offers an initial reference tolerance of 2% at 25C. An adjustable shunt regulator is a type of voltage reference IC that maintains a programmed voltage across its cathode-anode terminals by sinking current when the sense voltage at its reference pin exceeds an internal bandgap threshold. Within the power-management hierarchy it sits below linear regulators as a precision reference element, and it is widely used as the feedback error amplifier inside isolated and non-isolated switching power supplies. Key features of the TL431ILPR include a programmable output voltage set anywhere from Vref (approximately 2.5V) to 36V using just two external resistors, a sharp low-dynamic-output-impedance characteristic, low output noise, and a typical temperature coefficient in the low ppm/C range across the specified -40C to +85C industrial operating range. Its 1mA to 100mA sink-current range gives designers wide loop-gain control in optocoupler feedback networks. Technically, the TL431 combines an internal 2.495V bandgap reference with an open-collector-style error amplifier driving the cathode output. Because the reference input draws only about 2uA typical, high-impedance divider networks are practical. The device is stable with appropriate capacitive loading per the stability boundary in the manufacturer datasheet, and it is specified for thermal stability over automotive, commercial, and military temperature grades across the family. Typical applications include secondary-side voltage regulation in flyback and forward AC-DC power supplies, adjustable zener replacement in overvoltage protection Crowbar circuits, precision current-source and current-limiter biasing, and set-point generation in battery chargers. Its three-pin simplicity and low cost make it the industry default feedback element driving optocoupler LEDs in isolated converters. Design-wise, keep the cathode current above the 1mA minimum for regulation and respect the datasheet stability criteria when adding decoupling capacitance at the cathode node; the compensation capacitor interacts with the equivalent series resistance in ways that can destabilize the loop. This page synthesizes distributor pricing, drop-in cross-brand alternatives, pinout detail, and practical design notes not consolidated in the manufacturer datasheet.
TLV431IDBVR - 1.5% 6V Adj Shunt Reference | Texas Instruments
The Texas Instruments TLV431IDBVR is a low-voltage three-terminal adjustable precision shunt regulator providing a 1.24 V reference with ±1.5% initial accuracy and 15 mA maximum cathode current, housed in a 5-pin SOT-23 (DBV) package. Output voltage is programmable from VREF (1.24 V) to 6 V through two external resistors, enabling flexible rail design from sub-1.5 V point-of-load references up to small analog and digital supplies. The low minimum cathode current of 80 µA (typical) makes the part well suited to low-power and always-on circuits. A shunt voltage reference such as the TLV431 is functionally a two-terminal analog building block - when biased with a resistor from a higher supply, it conducts current through its cathode-to-anode path to hold its reference pin at the programmed voltage. As a category, voltage references sit alongside linear regulators, supervisors, and ADC/DAC references inside the power management IC hierarchy, and behave as programmable Zener diodes with much tighter tolerance and lower dynamic impedance than discrete components. They are the building blocks of closed-loop SMPS feedback, precision comparators, and adjustable linear regulators. Key features of the TLV431 family include 1.24 V typical reference with ±1.5% tolerance (the tighter TLV431A grade specifies ±1%), a wide programmable output range of VREF to 6 V, 80 µA typical minimum cathode current, low output impedance of 0.25 Ω typical, and operation across -40 °C to +85 °C industrial/commercial temperatures. The 5-pin SOT-23 (DBV) footprint enables drop-in replacement among TLV431 grades and competitor parts in the same pin-out. Architecturally, the TLV431 uses a bandgap-derived 1.24 V reference buffer, an internal error amplifier that compares the reference pin to VREF, and a pass transistor that sinks current to regulate the output. The wide cathode operating range and low dynamic impedance allow the regulator to maintain tight output regulation across load and supply variations typical of switching-supply feedback loops. Typical applications include switching-supply secondary-side feedback, adjustable linear regulator references, isolated point-of-load rails, precision comparator thresholds, and ADC/DAC reference circuits. Engineers may also use the TLV431 as a low-cost, low-power replacement for a TL431 where lower minimum cathode current and a smaller SOT-23-5 package are required. When designing with the TLV431, size the cathode bias resistor to keep the device above its minimum operating current (80 µA typical) under worst-case load, and add a capacitor on the reference pin if the application demands transient stability. Because the part ships in the small SOT-23-5 outline, expect to follow standard SMD PCB layout practices - minimize reference-pin leakage and route the cathode trace away from switching nodes. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on the manufacturer datasheet, giving engineers a single reference for sourcing, second-sourcing, and properly biasing the TLV431IDBVR in low-voltage reference designs.