Texas Instruments TLVH432AIDBZR

Overview

TLVH432AIDBZR from Texas Instruments is a low-voltage adjustable precision shunt regulator in SOT-23-3 package, providing 1.24 V reference voltage with ±1% initial tolerance at 25°C, 0.25 Ω typical dynamic impedance, and operation from 1.24 V to 18 V output range. It serves as an error amplifier or comparator with integrated reference in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH432AIDBZR datasheet, TLVH432AIDBZR pinout, TLVH432AIDBZR application, or TLVH432AIDBZR equivalent, key selection criteria include cathode current range (100 μA–70 mA), thermal stability (–40°C to +125°C), ultra-low reference input current (0.1–0.5 μA), and SOT-23-3 pin compatibility with TLVH431 variants.

Technical Context

The TLVH432AIDBZR implements a precision bandgap reference and high-gain transconductance amplifier in a 3-terminal shunt topology. Its internal architecture enables closed-loop regulation via resistive feedback between cathode and reference pins, or open-loop comparator operation with direct input on the reference pin.

Unlike the TLVH431, the TLVH432AIDBZR uses reversed pinout (REF–CATHODE–ANODE) in SOT-23-3, enabling layout flexibility in space-constrained secondary-side regulation circuits. It requires ≥100 μA cathode current for stable regulation and exhibits sharp turn-on characteristics due to active output circuitry.

Key Specifications

Pinout & Package

SOT-23-3 package (2.92 mm × 1.30 mm body size), surface-mount, RoHS-compliant, with gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH432AIDBZR, TLVH431AIDBZR offers identical performance but demands board-level pin mapping changes, while TLVH432ACDBZR trades higher cost for ±0.5% reference tolerance and improved thermal drift-critical in closed-loop systems where feedback gain depends on reference stability.

Availability

TLVH432AIDBZR is available at Aetrix Electronics and suitable for isolated SMPS design, precision voltage monitoring, and low-power comparator applications requiring stable component supply across automotive, industrial, and telecom end equipment.

Supply support for TLVH432AIDBZR 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, with leadership in precision analog, power management, and signal chain technologies.

The TLVH432AIDBZR belongs to TI's precision shunt regulator product line, designed specifically for low-voltage, high-accuracy feedback in isolated power supplies and voltage supervision circuits.

FAQ

What is the reference voltage tolerance of TLVH432AIDBZR at 25°C?

The TLVH432AIDBZR has a reference voltage tolerance of ±1% at 25°C, corresponding to a 1.24 V nominal V_REF with min/max values of 1.228 V and 1.252 V. This A-grade tolerance is specified per Section 5.6 of the SLVS555N datasheet and applies across all operating conditions unless otherwise noted.

Can TLVH432AIDBZR replace TL431 in existing designs?

TLVH432AIDBZR cannot directly replace TL431 due to its lower 1.24 V reference voltage (vs. 2.5 V), different pinout, and reduced cathode voltage headroom requirement. However, it can substitute TL431 in new low-voltage designs-such as 3.3 V or 2.5 V SMPS-where the feedback divider and optocoupler drive are redesigned to accommodate the 1.24 V reference point.

What is the minimum cathode current required for regulation in TLVH432AIDBZR?

The TLVH432AIDBZR requires a minimum cathode current of 100 μA to maintain regulation, as confirmed in Sections 5.5–5.7 of the datasheet. Below this level, gain drops significantly and regulation becomes unstable-especially at temperature extremes-so designs must ensure continuous IK ≥ 100 μA under all operating conditions.

Does TLVH432AIDBZR require an output capacitor for stability?

No, TLVH432AIDBZR is internally compensated and remains stable without an output capacitor between cathode and anode. This is explicitly stated in Section 7.3 and verified in Figure 5-15 through Figure 5-17. Capacitors may be added for noise filtering, but they are not required for loop stability in standard shunt regulator configurations.

How does the pinout of TLVH432AIDBZR differ from TLVH431AIDBZR?

TLVH432AIDBZR uses REF–CATHODE–ANODE pinout in SOT-23-3 (Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE), whereas TLVH431AIDBZR uses CATHODE–REF–ANODE (Pin 1 = CATHODE, Pin 2 = REF, Pin 3 = ANODE). This reversal enables optimized routing in compact flyback feedback paths but requires dedicated footprint layout for TLVH432AIDBZR.