Texas Instruments TLVH432CDBZT

Overview

TLVH432CDBZT from Texas Instruments is a low-voltage adjustable precision shunt regulator in SOT-23-3 package, providing 1.24 V reference voltage with ±0.5% initial tolerance (B-grade), 100 μA to 70 mA cathode current range, and operation from –40°C to +125°C. It functions as an integrated voltage reference and error amplifier in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH432CDBZT datasheet, TLVH432CDBZT pinout, TLVH432CDBZT application, or TLVH432CDBZT equivalent, key selection factors include its 1.24 V low-voltage reference, ultra-low 0.25 Ω dynamic impedance, SOT-23-3 pin-compatible alternative to TLVH431 with REF–CATHODE–ANODE pinout, and suitability for secondary-side regulation in 3.3 V/5 V power supplies.

Technical Context

The TLVH432CDBZT implements a precision bandgap reference and high-gain transconductance amplifier in a 3-terminal shunt topology. Its internal architecture forces the REF pin to 1.24 V relative to ANODE when sufficient cathode current (≥100 μA) flows, enabling closed-loop regulation via external resistor dividers.

Unlike the TLVH431, the TLVH432CDBZT uses a fixed REF–CATHODE–ANODE pinout in SOT-23-3 (Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE), eliminating ambiguity in PCB layout for feedback networks. It achieves 0.25 Ω typical dynamic impedance and maintains stable operation without output capacitance due to internal compensation.

Key Specifications

Pinout & Package

SOT-23-3 package (2.92 mm × 1.30 mm body size), surface-mount, lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431CDBZT, TLVH432CDBZT offers immediate pinout compatibility with REF-first feedback networks; compared with TLVH432IDBZT, it delivers tighter 0.5% reference accuracy and full automotive-grade temperature support - critical for high-reliability isolated power and precision measurement.

Availability

TLVH432CDBZT is available at Aetrix Electronics and suitable for isolated flyback SMPS design, precision ADC reference circuits, and rail voltage monitoring applications requiring stable component supply across long production lifecycles.

Supply support for TLVH432CDBZT 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 control ICs.

The TLVH432CDBZT belongs to TI's precision shunt regulator product line, engineered specifically for low-voltage, high-accuracy feedback in isolated DC/DC converters, data converter references, and intelligent power monitoring systems.

FAQ

What is the pin configuration of TLVH432CDBZT?

The TLVH432CDBZT uses a fixed 3-pin SOT-23 package with REF–CATHODE–ANODE pinout (Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE). This differs from TLVH431 variants and ensures consistent feedback network orientation. The ANODE terminal serves as the common reference point, and the REF pin requires connection to a resistor divider to set output voltage.

How does TLVH432CDBZT differ from TLVH431CDBZT?

TLVH432CDBZT and TLVH431CDBZT share identical electrical specifications and SOT-23-3 packaging but differ exclusively in pin assignment: TLVH432CDBZT is REF–CATHODE–ANODE (Pin 1–2–3), while TLVH431CDBZT is ANODE–CATHODE–REF (Pin 1–2–3). This makes them electrically interchangeable but not PCB-layout compatible without redesign.

What is the minimum cathode current required for regulation with TLVH432CDBZT?

The TLVH432CDBZT requires a minimum cathode current of 100 μA to maintain regulation across its full operating temperature range (–40°C to +125°C). Below this threshold, gain drops significantly, causing inaccurate reference tracking and potential instability in feedback loops.

Can TLVH432CDBZT replace a Zener diode directly?

Yes - TLVH432CDBZT functions as a programmable, low-leakage Zener replacement. With IK(off) ≤ 0.1 μA and sharp turn-on characteristics, it provides superior thermal stability (≤31 ppm/°C) and lower dynamic impedance (0.25 Ω) than standard Zeners, especially below 3.3 V. External resistors set the breakdown voltage from 1.24 V to 18 V.

Is an output capacitor required for stability with TLVH432CDBZT?

No - TLVH432CDBZT is internally compensated and operates stably 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 - typically ≤10 nF for 1.25 V VKA, ≤2.2 nF for 5 V VKA.