Texas Instruments TLVH432BCDBZR

Overview

TLVH432BCDBZR from Texas Instruments is a low-voltage adjustable precision shunt regulator with 0.5% reference voltage tolerance at 25°C, 1.24 V nominal reference voltage, and operation down to 1.24 V cathode-to-anode voltage. It delivers stable regulation across –40°C to +125°C, supports cathode currents from 100 μA to 70 mA, and features 0.25 Ω typical dynamic impedance-ideal for secondary-side feedback in isolated 3.3 V flyback SMPS designs.

For engineers reviewing the TLVH432BCDBZR datasheet, TLVH432BCDBZR pinout, TLVH432BCDBZR application, or TLVH432BCDBZR equivalent, key selection criteria include its B-grade accuracy, SOT-23-3 package pin configuration (REF–CATHODE–ANODE), ultra-low minimum cathode current requirement, and compatibility with optocoupler-based isolated feedback loops requiring tight voltage monitoring below 2.5 V.

Technical Context

The TLVH432BCDBZR 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 TLVH432BCDBZR uses a reversed pinout (REF–CATHODE–ANODE) in the SOT-23-3 (DBZ) package, optimizing PCB layout for compact flyback feedback networks. It operates stably without output capacitance but maintains phase margin ≥36° with capacitive loads up to 100 nF at 5 V cathode voltage.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: 2.92 mm × 1.30 mm body, gull-wing leads, JEDEC MO-178AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH432ACDBZR and TLVH431BCDBZR, the TLVH432BCDBZR offers the highest initial accuracy in the DBZ package while maintaining pin compatibility with other TLVH432 variants-making it optimal for new designs demanding precision without layout rework.

Availability

TLVH432BCDBZR is available at Aetrix Electronics and suitable for isolated power supplies, precision data acquisition systems, and embedded voltage monitoring circuits requiring stable component supply across automotive, industrial, and telecom end equipment.

Supply support for TLVH432BCDBZR 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 delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The TLVH432BCDBZR belongs to TI's precision shunt regulator product line, designed specifically for low-voltage, high-accuracy feedback and reference applications in space- and power-constrained systems.

FAQ

What is the reference voltage tolerance of TLVH432BCDBZR at 25°C?

The TLVH432BCDBZR has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal V_REF with a range of 1.234 V to 1.246 V. This B-grade accuracy is confirmed in Section 5.7 of the official datasheet and applies specifically to the TLVH432BCDBZR variant. The tolerance remains stable across temperature, with full-range deviation limited to 31 mV for the Q-grade (-40°C to +125°C) version.

How does TLVH432BCDBZR differ from TLVH431BCDBZR?

The TLVH432BCDBZR and TLVH431BCDBZR share identical electrical specifications-including V_REF, cathode current range, and thermal performance-but differ exclusively in SOT-23-3 pinout order. TLVH432BCDBZR uses REF–CATHODE–ANODE (Pin 1–2–3), while TLVH431BCDBZR uses CATHODE–ANODE–REF. This reversal affects PCB layout but not circuit functionality. Both are documented in TI's SLVS555N datasheet as pinout variants of the same core device family.

What is the minimum cathode current required for regulation in TLVH432BCDBZR?

The TLVH432BCDBZR requires a minimum cathode current of 100 μA to maintain regulation, as specified in Sections 5.5–5.7 of the datasheet under "I_K(min)". This value is guaranteed across the full operating temperature range and is lower than the TL431's 1 mA requirement-enabling use in ultra-low-power applications such as battery-backed monitoring circuits where current budget is constrained to microamps.

Can TLVH432BCDBZR operate without an output capacitor?

Yes, TLVH432BCDBZR is internally compensated and operates stably without an output capacitor between cathode and anode, unlike many linear regulators. This is explicitly stated in Section 7.3 of the datasheet. However, if an output capacitor is added for noise filtering or transient response improvement, Figures 5-15 through 5-17 provide phase-margin guidance for selecting values up to 100 nF depending on cathode voltage and load conditions.

What are the absolute maximum ratings for cathode voltage and current in TLVH432BCDBZR?

The absolute maximum cathode voltage (V_KA) for TLVH432BCDBZR is 20 V, and the absolute maximum cathode current (I_K) is 80 mA, per Section 5.1 of the datasheet. Exceeding these limits may cause permanent damage. For continuous operation, the recommended cathode voltage range is 1.24 V to 18 V, and the recommended cathode current is 100 μA to 70 mA-ensuring reliable performance within thermal and reliability boundaries.