Texas Instruments TLVH431ACDBVRE4

Overview

TLVH431ACDBVRE4 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, ±1% initial tolerance at 25°C (A-grade), and operation down to 1.24 V cathode-anode voltage. It delivers stable voltage reference and error amplification in isolated flyback SMPS feedback loops, data converter references, and power-rail monitoring circuits.

For engineers reviewing the TLVH431ACDBVRE4 datasheet, TLVH431ACDBVRE4 pinout, TLVH431ACDBVRE4 application, or TLVH431ACDBVRE4 equivalent, this page provides verified technical context, package-specific pin functions, real-world design meaning of key specs, and two confirmed alternative parts for voltage reference and shunt regulation use cases.

Technical Context

The TLVH431ACDBVRE4 implements a high-gain transconductance amplifier with an internal 1.24 V bandgap reference, enabling precise closed-loop shunt regulation or open-loop comparator operation. Its Darlington output stage supports sink currents from 100 µA to 70 mA while maintaining 0.25 Ω typical dynamic impedance.

It operates across –40°C to +125°C (Q-grade), requires no external compensation for stability, and achieves <0.5 µA reference input current - critical for high-impedance resistor-divider networks in low-power systems. The device's sharp turn-on characteristic and low leakage (<0.1 µA off-state cathode current) make it a direct functional replacement for low-voltage Zener diodes.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 5-pin surface-mount with exposed substrate connection on Pin 2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVRE4, TLVH431BIDBVRE4 offers tighter initial tolerance without layout change, while TLV431ACDBVR reduces cost at the expense of temperature range and substrate handling - making TLVH431ACDBVRE4 the optimal balance of precision, ruggedness, and manufacturability for demanding embedded power systems.

Availability

TLVH431ACDBVRE4 is available at Aetrix Electronics and suitable for isolated SMPS feedback, precision data converter references, and power-rail monitoring applications requiring stable component supply across automotive, industrial, and telecom end equipment.

Supply support for TLVH431ACDBVRE4 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in precision reference and power IC design.

The TLVH431 family was designed specifically for low-voltage, high-accuracy shunt regulation in isolated power supplies and precision analog systems - addressing limitations of legacy TL431 devices in sub-2 V applications.

FAQ

What is the reference voltage tolerance of TLVH431ACDBVRE4 at 25°C?

The TLVH431ACDBVRE4 has a reference voltage tolerance of ±1% at 25°C, corresponding to a V_REF range of 1.228 V to 1.252 V. This A-grade specification is confirmed in Section 5.6 of the TI datasheet SLVS555N and applies specifically to the AC suffix variant in the DBV package. TLVH431ACDBVRE4 maintains this tolerance across its full operating temperature range when used within recommended conditions.

Can TLVH431ACDBVRE4 replace a standard Zener diode in low-voltage circuits?

Yes, TLVH431ACDBVRE4 is explicitly designed as a low-leakage, adjustable Zener replacement - supporting cathode voltages as low as 1.24 V with off-state current as low as 0.02 µA. Its sharp turn-on characteristic and 0.25 Ω dynamic impedance provide superior regulation accuracy compared to discrete Zeners below 3.3 V. TLVH431ACDBVRE4 requires only two external resistors to set output voltage, eliminating the need for multiple fixed-Zener parts.

What is the minimum cathode current required for regulation in TLVH431ACDBVRE4?

The TLVH431ACDBVRE4 requires a minimum cathode current (I_K(min)) of 100 µA to maintain regulation, as specified in Sections 5.5–5.7 of the datasheet. This value holds across the full –40°C to +125°C temperature range. Operating below this threshold risks loss of regulation accuracy and reduced open-loop gain, especially in comparator-mode applications. TLVH431ACDBVRE4's 100 µA requirement is one-tenth that of TL431, enabling ultra-low-power designs.

Does TLVH431ACDBVRE4 require an output capacitor for stability?

No, TLVH431ACDBVRE4 is internally compensated and stable without an output capacitor between cathode and anode - a key advantage over many linear regulators. This eliminates capacitor-related aging, ESR drift, and layout sensitivity. However, if an output capacitor is used for noise filtering, Figures 5-15 through 5-17 in the datasheet provide phase-margin guidance for selecting values up to 10 nF depending on cathode voltage and load conditions.

What is the function of Pin 2 (substrate) on the TLVH431ACDBVRE4 SOT-23-5 package?

Pin 2 on TLVH431ACDBVRE4 is the internal die substrate connection and must be tied to the ANODE (Pin 5) or left electrically floating - it is not a signal pin. This connection establishes the thermal and electrical reference plane for the silicon die. Leaving Pin 2 unconnected or shorting it to CATHODE (Pin 3) may cause instability or parametric shift. The requirement is explicitly documented in the "Pin Functions" table of the SLVS555N datasheet for the DBV package.