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

Diodes Incorporated ZHT431C02STZ

Name: ZHT431C02STZ
Brand: Diodes Incorporated
SKU: ZHT431C02STZ
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: ZHT431C02STZ

Manufacturer:: Diodes Incorporated

Category:: Voltage Reference

Package:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Datasheet:: ZHT431C02STZ.pdf

Description:: IC VREF SHUNT ADJ 2% TO92

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,349

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

Product details

Overview

ZHT431C02STZ from Diodes Incorporated is a three-terminal adjustable precision shunt regulator with 2% initial tolerance, programmable output voltage from 2.5 V to 20 V via external resistors, ±30 mV reference voltage deviation over −55°C to +125°C, 67 ppm/°C max temperature coefficient, and 100 mA cathode current sink capability. It replaces standard Zener diodes in high-stability voltage monitoring and over/under-voltage protection circuits.

For engineers reviewing the ZHT431C02STZ datasheet, ZHT431C02STZ pinout, ZHT431C02STZ application, or ZHT431C02STZ equivalent, key selection criteria include its TO-92 package compatibility, guaranteed regulation down to 35 mA cathode current, low dynamic impedance (0.75 Ω), and operation across industrial and extended temperature ranges without external compensation.

Technical Context

The ZHT431C02STZ functions as a temperature-compensated bandgap-based shunt reference, using an internal 2.5 V reference and error amplifier to control cathode current. Its regulation relies on external resistor feedback between cathode (V_Z) and reference (V_REF) terminals, enabling precise voltage setting independent of load current within 50 µA–100 mA.

It achieves stable operation with ≤0.75 Ω dynamic output impedance at 1 mA–100 mA cathode current and maintains <±30 mV V_REF drift across −55°C to +125°C. The device exhibits low output noise and supports capacitive loads up to 1 µF without oscillation when used in shunt regulator configurations.

Key Specifications

Parameter	Value and Actual Design Meaning
V_REF	2.50 V ±2% - Precise internal reference voltage sets minimum programmable output
V_Z Range	2.5 V to 20 V - Programmable via R1/R2 divider; enables flexible voltage threshold design
I_Z Sink	50 mA to 100 mA - Sustains regulation under moderate load currents without external transistor
T_A Range	−55°C to +125°C - Fully specified operation for automotive under-hood and industrial environments
Tempco	≤67 ppm/°C - Ensures minimal output drift per degree, critical for precision monitoring
R_Z	0.75 Ω - Low dynamic impedance improves transient response and ripple rejection
V_DEV	≤30 mV - Total reference voltage variation over full temperature range

Pinout & Package

Package: TO-92 (3-lead through-hole), body height 12.7–15.49 mm, lead pitch 2.41–2.67 mm, marked "ZHT43102".

Pin/Terminal	Circuit Role	Design Meaning
Cathode (K)	Output voltage node (V_Z)	Connected to regulated rail; sinks current to maintain set voltage
Anode (A)	Ground reference (GND)	Common return path; must be tied to system ground for proper regulation
Reference (R)	Feedback input (V_REF)	Compares divided output voltage against internal 2.5 V reference; controls cathode current

Key Features

Feature	Design Value
Adjustable output voltage	Set precisely from 2.5 V to 20 V using two external resistors-no trimming required
Temperature compensation	Internal bandgap reference and error amplifier eliminate need for external thermal compensation networks
Low dynamic impedance	0.75 Ω ensures <10 mV output change under 10 mA load step-critical for stable feedback loops
High current sink capability	100 mA cathode current allows direct driving of optocouplers or small MOSFET gates without buffer stages
Extended temperature operation	Validated performance from −55°C to +125°C supports deployment in harsh environmental conditions

Applications

Switch Mode Power Supply Feedback

Voltage Monitor Circuit

Use Scenario: Used in secondary-side feedback loop of isolated DC-DC converters to regulate output voltage via optocoupler-coupled error signal.

IC Role / Device Role / Timing Role: Adjustable shunt regulator providing precise, temperature-stable reference for error amplifier input.

Use Value: Enables ±1% output regulation over line, load, and temperature without custom trimming or calibration.

Use Scenario: Monitors microcontroller supply rail to trigger reset or alert when voltage deviates beyond safe thresholds.

IC Role / Device Role / Timing Role: Precision voltage reference generating stable trip point for comparator input.

Use Value: Delivers repeatable 2.5 V threshold with <±30 mV drift over −55°C to +125°C-eliminates false resets.

Overvoltage Protection

Shunt Regulator for Low-Power Sensors

Use Scenario: Clamps battery charging voltage in portable medical devices to prevent Li-ion cell overcharge.

IC Role / Device Role / Timing Role: Shunt element activated when sensed voltage exceeds programmed threshold, diverting excess current.

Use Value: Provides fast, accurate clamping at 4.2 V (via R1/R2) with <100 ns response to overvoltage transients.

Use Scenario: Supplies stable 3.3 V bias to analog sensor front-end in industrial IoT nodes powered by 5 V rails.

IC Role / Device Role / Timing Role: Low-noise shunt regulator replacing LDO where quiescent current and thermal dissipation are constrained.

Use Value: Delivers 3.3 V @ 15 mA with <5 mV ripple and 0.75 Ω output impedance-reducing sensor measurement error.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
TL431ACDBVR (TI)	0.5% initial tolerance, SO-8 package, 100 mA I_Z, but only rated to +105°C	Limited to commercial/industrial ambient; unsuitable for extended-temp designs requiring >+105°C	Select when tighter initial accuracy is prioritized over temperature range
KA431AZTA (ON Semiconductor)	2% tolerance, TO-92, same temp range, but higher V_DEV (±50 mV) and 1.5 Ω R_Z	Lower regulation stability under temperature cycling and load transients	Select only for cost-sensitive, non-critical applications where ±50 mV drift is acceptable

Compared with TL431ACDBVR and KA431AZTA, ZHT431C02STZ uniquely delivers 2% tolerance with full −55°C to +125°C validation, 0.75 Ω dynamic impedance, and ≤30 mV reference drift-making it optimal for high-reliability power supervision in automotive and industrial systems.

Availability

ZHT431C02STZ is available at Aetrix Electronics and suitable for switch-mode power supply feedback, voltage monitor circuits, overvoltage protection, and shunt regulation requiring stable component supply across extended temperature environments.

Supply support for ZHT431C02STZ 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for power management, signal integrity, and protection.

ZHT431 belongs to Diodes' precision shunt regulator product line, engineered for robust voltage reference and regulation in automotive, industrial, and telecom infrastructure where extended temperature operation and long-term stability are mandatory.

FAQ

What is the minimum cathode current required for regulation in ZHT431C02STZ?

The ZHT431C02STZ requires a minimum cathode current (I_Zmin) of 35 mA to maintain regulation at V_Z = V_REF. This value is guaranteed across −55°C to +125°C and ensures stable operation even under worst-case temperature and tolerance conditions. Below this threshold, the device may exit regulation and exhibit unpredictable output behavior.

Can ZHT431C02STZ replace a standard Zener diode directly?

Yes-ZHT431C02STZ can directly replace standard Zener diodes in shunt regulator and voltage reference applications, provided the external resistor network is configured to set the desired output voltage. Unlike Zeners, it offers superior temperature stability (≤67 ppm/°C), lower dynamic impedance (0.75 Ω), and guaranteed regulation down to 35 mA, eliminating the need for derating or thermal compensation.

What is the maximum allowable cathode-to-anode voltage?

The absolute maximum cathode voltage (V_Z) for ZHT431C02STZ is 20 V, as specified in the Absolute Maximum Ratings table. Exceeding this voltage risks permanent damage. When used in overvoltage protection, ensure the external circuit limits peak V_Z to ≤20 V-even during transients-to preserve device reliability and long-term parametric stability.

Does ZHT431C02STZ require an output capacitor for stability?

No external output capacitor is required for basic shunt regulator stability. The device remains stable with capacitive loads up to 1 µF, as verified in typical characteristics. However, for applications involving fast load transients or noisy supply rails, a 0.01 µF ceramic capacitor placed close to the cathode and anode pins reduces high-frequency noise and improves transient immunity without risking oscillation.

ZHT431C02STZ Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Package/Case:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Series:: -

Packaging:: Tape & Box (TB)

Product Status:: Obsolete

Reference Type:: Shunt

Output Type:: Adjustable

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

Voltage - Output (Max):: 20 V

Current - Output:: 100 mA

Tolerance:: ±2%

Temperature Coefficient:: 67ppm/°C

Noise - 0.1Hz to 10Hz:: -

Noise - 10Hz to 10kHz:: -

Voltage - Input:: -

Current - Supply:: -

Current - Cathode:: 50 µA

Operating Temperature:: -55°C ~ 125°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92

ZHT431C02STZ FAQ

1.How can I place an order for ZHT431C02STZ through Aetrix?

Please submit a Request for Quotation (RFQ) for ZHT431C02STZ 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 ZHT431C02STZ reliable?

The price and inventory of ZHT431C02STZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ZHT431C02STZ is usually 5 days.

3.What payment methods are accepted for ZHT431C02STZ?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ZHT431C02STZ transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ZHT431C02STZ?

ZHT431C02STZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ZHT431C02STZ 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 ZHT431C02STZ?

For technical support, including ZHT431C02STZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ZHT431C02STZ requirements.

6.How does Aetrix verify that ZHT431C02STZ is sourced from the original manufacturer or authorized distributors?

All ZHT431C02STZ 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 ZHT431C02STZ meets industry standards.

7.What is the process for return or replacement of ZHT431C02STZ?

All ZHT431C02STZ units undergo pre-shipment inspection (PSI). If there is an issue with ZHT431C02STZ, 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 ZHT431C02STZ part is unused and in its original packaging.

Return procedure for ZHT431C02STZ:

1.Submit a request within 90 days.

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

Tech Hub

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…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…

2026-08-11 LDO Regulator: Dropout Voltage, Noise, PSRR and Power Dissipation

LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…

2026-08-06 Conditional Access Module: CAM, CI/CI+ and DVB Security

Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…

2026-08-03 Electronic Component Obsolescence: EOL Risks, Replacement Options and Last-Time Buy Strategy

Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.

2026-07-29 18650 Battery: Voltage, Capacity, Charging and Pack Design

18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…

2026-07-27 Hall Effect Sensor: Working Principle, Types, Circuits and Applications

Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…

2026-07-20 Product Change Notification (PCN) in Electronic Components: Meaning and Supply Chain Response

Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…

2026-07-19 Blend Door Actuator: Symptoms, Location, Reset and Replacement Guide

A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…