Texas Instruments TLVH432ACDBZR

Overview

TLVH432ACDBZR from Texas Instruments is a low-voltage adjustable precision shunt regulator in SOT-23-3 package, featuring 1.24 V reference voltage with ±0.5% initial tolerance (A grade), 100 μA to 70 mA cathode current range, 0.25 Ω typical dynamic impedance, and operation from –40°C to +125°C. It serves as an integrated voltage reference and error amplifier in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH432ACDBZR datasheet, TLVH432ACDBZR pinout, TLVH432ACDBZR application, or TLVH432ACDBZR equivalent, key selection considerations include its 3-pin SOT-23 pin configuration (REF–CATHODE–ANODE), 1.24 V low-voltage reference capability, ultra-low reference input current (0.1–0.5 μA), and suitability for secondary-side regulation in 3.3 V and lower isolated power supplies.

Technical Context

The TLVH432ACDBZR implements a precision bandgap reference with high-gain transconductance amplifier driving a Darlington sink output stage. Its internal architecture enables sharp turn-on behavior and stable closed-loop regulation without external compensation when used with resistive feedback networks.

Unlike the TLVH431, the TLVH432ACDBZR uses a distinct pinout (Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE) optimized for simplified PCB layout in compact power supply designs. This variant maintains identical electrical specifications-including 1.24 V reference, 0.25 Ω dynamic impedance, and 100 μA minimum cathode current-but differs exclusively in terminal assignment.

Key Specifications

Pinout & Package

SOT-23-3 package (2.92 mm × 1.30 mm body size) with gull-wing leads; RoHS-compliant, surface-mountable, and compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH432ACDBZR, TLVH431ACDBZR demands board-level pinout changes while delivering identical regulation performance, whereas TLVH432BIDBZR trades 0.5% reference accuracy for cost reduction-making it suitable for non-critical voltage monitoring where ±1% is sufficient.

Availability

TLVH432ACDBZR is available at Aetrix Electronics and suitable for isolated power supplies, precision data acquisition systems, and embedded voltage monitoring circuits requiring stable component supply and long-term manufacturability.

Supply support for TLVH432ACDBZR 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 company specializing in analog and embedded processing technologies, with leadership in precision analog ICs and power management solutions.

The TLVH432ACDBZR belongs to TI's precision shunt regulator product line, engineered specifically for low-voltage, high-accuracy feedback in space-constrained isolated power supplies and portable instrumentation.

FAQ

What is the pin configuration of TLVH432ACDBZR?

The TLVH432ACDBZR uses a 3-pin SOT-23 package with Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE. This pinout differs from TLVH431 variants and must be verified against PCB footprint before layout. The REF pin is high-impedance and requires connection to a resistor divider; CATHODE sinks current to regulate voltage; ANODE serves as the common return path.

How does TLVH432ACDBZR differ from TLVH431ACDBZR?

The TLVH432ACDBZR and TLVH431ACDBZR share identical electrical specifications-including 1.24 V reference voltage, ±0.5% tolerance, and –40°C to +125°C operation-but differ exclusively in pin assignment. TLVH432ACDBZR uses REF–CATHODE–ANODE, while TLVH431ACDBZR uses REF–ANODE–CATHODE. This makes them electrically interchangeable only with PCB layout modification.

Can TLVH432ACDBZR operate below 1.24 V?

No, TLVH432ACDBZR cannot regulate below its internal reference voltage of 1.24 V. Its minimum output voltage equals V_REF, and adjustable output ranges from 1.24 V to 18 V using external resistors. Attempting to force output below 1.24 V results in loss of regulation and uncontrolled cathode current.

What is the minimum cathode current required for regulation in TLVH432ACDBZR?

The TLVH432ACDBZR requires a minimum cathode current of 100 μA to maintain regulation across its full temperature range. Below this level, open-loop gain drops significantly, causing poor regulation accuracy and delayed response. Designers must ensure external bias networks supply ≥100 μA under worst-case conditions including temperature extremes and component tolerances.

Is an output capacitor required for stability with TLVH432ACDBZR?

No, TLVH432ACDBZR is internally compensated and stable without an output capacitor between CATHODE and ANODE. However, if added for noise filtering or transient suppression, capacitor value must be selected per TI's phase margin curves (Figures 5-15 to 5-17) to avoid oscillation-especially with capacitive loads exceeding 1 nF.