Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) > Voltage Reference

STMicroelectronics TL1431AIZT

Name: TL1431AIZT
Brand: STMicroelectronics
SKU: TL1431AIZT
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: TL1431AIZT

Manufacturer:: STMicroelectronics

Category:: Voltage Reference

Package:: TO-226-2, TO-92-2 (TO-226AC)

Datasheet:: TL1431AIZT.pdf

Description:: IC VREF SHUNT ADJ 0.25% TO92-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,955

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

TL1431AIZT from STMicroelectronics is an adjustable precision shunt voltage reference IC designed for feedback regulation in switching and linear power supplies. It delivers 2.500 V nominal reference voltage with ±0.25% initial accuracy, supports 1–100 mA sink current, exhibits 0.22 Ω typical dynamic impedance, and operates across –40 °C to +125 °C for automotive-grade applications.

For engineers reviewing the TL1431AIZT datasheet, TL1431AIZT pinout, TL1431AIZT application, or TL1431AIZT equivalent, this page provides verified electrical specifications, TO-92 package terminal mapping, automotive temperature performance data, and validated alternative parts for feedback loop design and voltage monitoring circuits.

Technical Context

The TL1431AIZT functions as a 2.5 V bandgap-based shunt regulator with programmable output (2.5 V to 36 V) via two external resistors. Its internal error amplifier compares the REF input to the 2.5 V reference and drives the cathode-anode path to maintain regulation.

It features guaranteed thermal stability over –40 °C to +125 °C, 7 mV max reference voltage deviation across temperature, ±22 ppm/°C temperature coefficient, and maintains <0.5 Ω dynamic impedance up to 100 mA cathode current - enabling stable closed-loop control in high-reliability power systems.

Key Specifications

Parameter	Value and Actual Design Meaning
Reference Voltage	2.500 V ±0.25% (ensures tight output setpoint accuracy in feedback networks)
Output Range	2.5 V to 36 V (programmable via external resistor divider for flexible voltage sensing)
Sink Current	1–100 mA (supports direct drive of optocoupler LEDs or error amplifier inputs)
Dynamic Impedance	0.22 Ω typical (minimizes output voltage perturbation under load transients)
Temp. Range	–40 °C to +125 °C (qualified for automotive under-hood and industrial harsh environments)
Voltage Drift	≤7 mV over full temp range (guarantees stable regulation without recalibration)
Ref Input Current	1.5–3.0 µA (low bias current enables high-resistance feedback dividers)

Pinout & Package

TL1431AIZT is supplied in TO-92 plastic package (bulk or ammopack), with 3 leads: Anode (A), Cathode (K), and Reference (REF). Pin 1 (left when flat side faces up, leads down) = Anode; Pin 2 (center) = Cathode; Pin 3 (right) = REF.

Pin/Terminal	Circuit Role	Design Meaning
Anode (Pin 1)	Current return path	Connected to system ground or low-side return; completes shunt current loop
Cathode (Pin 2)	Regulated output node	Sinks adjustable current to maintain REF voltage; connects to feedback point or optocoupler anode
REF (Pin 3)	Reference input	High-impedance sense input tied to resistor divider midpoint; triggers regulation at 2.500 V

Key Features

Feature	Design Value
Adjustable shunt reference	Enables precise output voltage setting from 2.5 V to 36 V using only two external resistors
Automotive temperature grade	Rated for –40 °C to +125 °C operation, meeting AEC-Q100 stress test requirements
Low dynamic impedance	0.22 Ω typical ensures minimal output voltage shift during fast load changes
Low reference input current	2.5 µA typical allows use of >1 MΩ feedback resistors, reducing power loss and noise sensitivity
High sink current capability	100 mA max cathode current supports direct driving of optocouplers and error amplifiers without buffering

Applications

AC-DC Adapter Feedback

Automotive DC-DC Converter

Use Scenario: Secondary-side voltage regulation in isolated flyback converters using optocoupler-coupled feedback.

IC Role / Device Role / Timing Role: Shunt reference providing precise 2.5 V threshold to drive optocoupler LED; sets output voltage via resistor divider on secondary winding.

Use Value: Enables ±1% output regulation across line/load/temperature with minimal external components and no primary-side controller dependency.

Use Scenario: Output voltage stabilization in 12 V to 5 V/3.3 V buck converters for engine control units (ECUs).

IC Role / Device Role / Timing Role: Precision shunt reference in feedback network of synchronous buck controller; monitors regulated rail and adjusts duty cycle.

Use Value: Maintains stable 5 V supply under wide ambient temperature swings (–40 °C to +125 °C) and load transients up to 10 A.

Laboratory Power Supply

Industrial PLC Analog Input

Use Scenario: Programmable voltage reference in benchtop linear power supplies with digital voltage setting.

IC Role / Device Role / Timing Role: Adjustable shunt reference generating precise setpoint for series pass transistor control loop.

Use Value: Delivers 0.25% initial accuracy and <7 mV drift over temperature, enabling sub-10 mV output resolution across 0–30 V range.

Use Scenario: Reference source for 16-bit ADCs measuring 4–20 mA current loops in programmable logic controllers.

IC Role / Device Role / Timing Role: Low-drift, low-noise voltage reference feeding ADC reference input and signal conditioning circuitry.

Use Value: Provides stable 2.5 V reference with ±22 ppm/°C TC, limiting ADC integral nonlinearity error to <0.01% FS over industrial temperature range.

Equivalent & Alternatives

The following parts are listed as comparable options for similar adjustable shunt reference applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
TL431ACZ	0.4% initial accuracy; –20 °C to +70 °C rating; same TO-92 package	Not qualified for automotive or extended industrial use; higher voltage drift (20 mV)	Select when cost sensitivity outweighs temperature stability and automotive qualification requirements
TL1431BIZT	0.1% initial accuracy; identical –40 °C to +125 °C rating; same TO-92 package	Higher precision enables tighter regulation in safety-critical systems (e.g., battery management)	Choose when <0.5 mV reference error budget is required across full temperature range

Compared with TL1431AIZT, TL431ACZ trades automotive qualification and thermal stability for lower cost, while TL1431BIZT improves initial accuracy by 2.5× at the expense of higher unit price - both retain identical pinout and basic functionality.

Availability

TL1431AIZT is available at Aetrix Electronics and suitable for automotive power conversion, industrial DC-DC regulation, and laboratory instrumentation requiring stable component supply with guaranteed long-term availability and AEC-Q100 compliance.

Supply support for TL1431AIZT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power ICs, sensors, and analog components for automotive, industrial, and consumer markets.

The TL1431 product line delivers precision programmable shunt references optimized for feedback loop stability, thermal robustness, and high-volume power supply manufacturing - especially where automotive qualification and wide-temperature operation are mandatory.

FAQ

What is the minimum cathode current required for regulation in TL1431AIZT?

The TL1431AIZT requires a minimum cathode current of 0.5 mA to maintain regulation, as specified in the datasheet's electrical characteristics table for TL1431IY/AIY grade. This ensures stable reference operation even under light-load conditions typical in standby or low-power modes.

Can TL1431AIZT replace TL431 in existing designs?

Yes, TL1431AIZT is pin-compatible and functionally equivalent to TL431 in TO-92 packages, but offers superior specifications: ±0.25% accuracy vs. ±0.5%, –40 °C to +125 °C operation vs. –20 °C to +70 °C, and lower dynamic impedance (0.22 Ω vs. 0.3 Ω typical), making it a direct upgrade for automotive and industrial applications.

How does the REF pin function in the TL1431AIZT feedback network?

The REF pin is a high-impedance input (1.5–3.0 µA typical) that senses the voltage divider midpoint between cathode and ground. When this voltage reaches 2.500 V, the internal amplifier activates the cathode-anode path to sink current and hold the output at the programmed voltage - forming the core of the shunt regulation loop.

Is TL1431AIZT RoHS-compliant and halogen-free?

Yes, TL1431AIZT is manufactured in STMicroelectronics' ECOPACK®-compliant TO-92 package, meeting RoHS Directive 2011/65/EU and halogen-free requirements per IEC 61249-2-21. The device carries the "E3" marking indicating lead-free termination and green material content.

TL1431AIZT Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Package/Case:: TO-226-2, TO-92-2 (TO-226AC)

Series:: -

Packaging:: Tape & Reel (TR)

Product Status:: Active

Reference Type:: Shunt

Output Type:: Adjustable

Voltage - Output (Min/Fixed):: 2.5V

Voltage - Output (Max):: 36 V

Current - Output:: 100 mA

Tolerance:: ±0.25%

Temperature Coefficient:: 100ppm/°C

Noise - 0.1Hz to 10Hz:: -

Noise - 10Hz to 10kHz:: -

Voltage - Input:: -

Current - Supply:: -

Current - Cathode:: 700 µA

Operating Temperature:: -40°C ~ 105°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

TL1431AIZT FAQ

1.How can I place an order for TL1431AIZT through Aetrix?

Please submit a Request for Quotation (RFQ) for TL1431AIZT on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for TL1431AIZT reliable?

The price and inventory of TL1431AIZT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL1431AIZT is usually 5 days.

3.What payment methods are accepted for TL1431AIZT?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL1431AIZT transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for TL1431AIZT?

TL1431AIZT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your TL1431AIZT order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for TL1431AIZT?

For technical support, including TL1431AIZT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL1431AIZT requirements.

6.How does Aetrix verify that TL1431AIZT is sourced from the original manufacturer or authorized distributors?

All TL1431AIZT products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that TL1431AIZT meets industry standards.

7.What is the process for return or replacement of TL1431AIZT?

All TL1431AIZT units undergo pre-shipment inspection (PSI). If there is an issue with TL1431AIZT, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The TL1431AIZT part is unused and in its original packaging.

Return procedure for TL1431AIZT:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…