Diodes Incorporated ZHT431F01TC

Overview

ZHT431F01TC from Diodes Incorporated is an adjustable precision shunt regulator in SOT23 (Type DN) package, functioning as a programmable 2.5–20 V voltage reference with 1% initial tolerance, 67 ppm/°C max temperature coefficient, and 50–100 mA cathode current capability. It replaces discrete Zener diodes in high-stability feedback loops for DC-DC converters, overvoltage monitors, and industrial power supplies operating from –55°C to +125°C.

For engineers reviewing the ZHT431F01TC datasheet, ZHT431F01TC pinout, ZHT431F01TC application, or ZHT431F01TC equivalent, key selection criteria include its programmable output voltage range, low dynamic impedance (≤0.75 Ω), tight thermal drift, wide operating temperature envelope, and SOT23 surface-mount compatibility for space-constrained power management designs.

Technical Context

The ZHT431F01TC implements a bandgap-referenced, temperature-compensated shunt regulation architecture that maintains stable reference voltage across –55°C to +125°C without external compensation. Its internal circuitry delivers <30 mV reference voltage deviation over full temperature range and supports programmable output via two external resistors.

It operates as a three-terminal current sink: cathode (VZ) sinks up to 100 mA, reference (VREF) senses the divider node, and anode (GND) provides return path. Dynamic impedance remains ≤0.75 Ω at 1–100 mA, enabling fast transient response in closed-loop feedback applications such as SMPS error amplifiers and voltage supervisors.

Key Specifications

Pinout & Package

SOT23 (Type DN) surface-mount package with 3-pin configuration: compact 2.8 mm × 2.4 mm footprint, 0.95 mm pitch, and 0.3 mm nominal lead length-optimized for automated assembly and thermal performance in high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL431CDBVR and KIA431AP, ZHT431F01TC offers tighter 1% tolerance and lower 67 ppm/°C temperature coefficient-critical for maintaining regulation accuracy in automotive and industrial systems where ambient temperature swings exceed 100°C.

Availability

ZHT431F01TC is available at Aetrix Electronics and suitable for switch-mode power supplies, voltage monitoring systems, overvoltage protection circuits, and linear post-regulators requiring stable component supply across extended temperature ranges.

Supply support for ZHT431F01TC 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 power management, signal integrity, and protection solutions.

The ZHT431 belongs to Diodes' precision shunt regulator product line, engineered for industrial, automotive, and telecom applications demanding robust thermal performance and long-term stability without external calibration.

FAQ

What is the minimum cathode current required for regulation?

The ZHT431F01TC requires a minimum cathode current of 35 µA to maintain regulation at VZ = VREF. This low turn-on threshold enables reliable operation in high-impedance feedback networks where current is limited by large-value divider resistors, ensuring stable reference behavior even at microamp-level bias conditions.

Can ZHT431F01TC replace a standard Zener diode directly?

Yes-ZHT431F01TC can directly replace standard Zener diodes in shunt regulator and voltage reference applications. Its three-terminal configuration requires only two external resistors to set output voltage, while delivering superior temperature stability, tighter tolerance, and lower dynamic impedance than typical Zeners-no circuit redesign needed beyond adding the reference pin connection.

What is the maximum power dissipation at 25°C ambient?

At TA = +25°C, the ZHT431F01TC has a maximum power dissipation of 330 mW. Derating begins at 2.2 mW/°C above 25°C, reaching zero dissipation at +175°C junction temperature. This rating assumes proper PCB copper area and thermal vias per Diodes' recommended pad layout for SOT23 (Type DN) packages.

Is ZHT431F01TC RoHS and halogen-free compliant?

Yes-ZHT431F01TC is fully RoHS 3 compliant (2015/863/EU), lead-free, and halogen-free per Diodes' "Green" definition: <900 ppm bromine, <900 ppm chlorine (<1500 ppm Br+Cl total), <1000 ppm antimony, and <1000 ppm beryllium-verified in manufacturing and documented in Diodes' quality certifications.