Texas Instruments TLVH432BCPK

Overview

TLVH432BCPK from Texas Instruments is a low-voltage adjustable precision shunt regulator in SOT-89-3 package, featuring 1.24 V reference voltage (±0.5% at 25°C), 100 μA to 70 mA cathode current range, and operation from –40°C to +125°C. It functions as a programmable voltage reference or comparator with integrated reference in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH432BCPK datasheet, TLVH432BCPK pinout, TLVH432BCPK application, or TLVH432BCPK equivalent, key selection criteria include its B-grade reference tolerance, SOT-89 thermal performance (R_θJA = 52°C/W), ultra-low 0.25 Ω dynamic impedance, and compatibility with optocoupler-based secondary-side regulation circuits requiring stable sub-3.3 V references.

Technical Context

The TLVH432BCPK implements a three-terminal shunt-regulator architecture with an internal 1.24 V bandgap reference and high-gain transconductance amplifier driving a Darlington output stage. Its open-loop operation supports comparator functionality with built-in reference, while closed-loop configuration enables precise voltage regulation via external resistor dividers.

Unlike the TLVH431, the TLVH432BCPK uses reversed pinout in SOT-89: Pin 1 = CATHODE, Pin 2 = ANODE, Pin 3 = REF - enabling direct replacement in layouts where anode-grounded topology simplifies PCB routing and improves thermal coupling to heatsink pads.

Key Specifications

Pinout & Package

SOT-89-3 package (4.50 mm × 2.50 mm body) with exposed thermal pad; optimized for surface-mount assembly and thermal dissipation in power-constrained designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH432BCPK, TLVH432BIDBZR trades thermal performance for compactness, while TLVH431BCPK retains identical thermal capability but mandates pinout-aware layout changes - making TLVH432BCPK optimal for new designs prioritizing power density and thermal reliability in isolated power feedback paths.

Availability

TLVH432BCPK is available at Aetrix Electronics and suitable for isolated flyback SMPS, precision data converter references, and automotive voltage monitoring applications requiring stable component supply across extended temperature ranges.

Supply support for TLVH432BCPK 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 TLVH432BCPK belongs to TI's precision shunt regulator product line, designed specifically for low-voltage, high-accuracy voltage reference and error amplification in isolated power supplies and measurement systems.

FAQ

What is the reference voltage tolerance of TLVH432BCPK at 25°C?

The TLVH432BCPK has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal V_REF with min/max values of 1.234 V and 1.246 V. This B-grade accuracy is confirmed in Section 5.7 of the official datasheet and applies specifically to the TLVH432BCPK variant across its SOT-89 package and full operating temperature range.

How does the TLVH432BCPK pinout differ from TLVH431 in SOT-89 package?

The TLVH432BCPK uses Pin 1 = CATHODE, Pin 2 = ANODE, Pin 3 = REF in SOT-89, whereas TLVH431BCPK uses Pin 1 = REF, Pin 2 = ANODE, Pin 3 = CATHODE. This reversed pinout is explicitly documented in Figure 4-7 and the Pin Functions table of the datasheet, enabling direct integration into anode-grounded topologies without signal inversion.

What is the minimum cathode current required for regulation in TLVH432BCPK?

The TLVH432BCPK requires a minimum cathode current of 100 μA to maintain regulation, as specified in Section 5.5 (IK(min)) of the datasheet. This value is guaranteed over the full –40°C to +125°C temperature range and is independent of output voltage setting within the 1.24 V to 18 V range.

Can TLVH432BCPK operate without an output capacitor?

Yes, TLVH432BCPK is internally compensated and stable without an output capacitor between cathode and anode, as stated in Section 7.3. This eliminates mandatory capacitance in basic shunt configurations, though capacitive loads up to 10 nF can be used with phase margin guidance from Figures 5-15 to 5-17 when enhanced transient response is needed.

What thermal resistance does TLVH432BCPK exhibit in SOT-89 package?

The TLVH432BCPK in SOT-89 package has a junction-to-ambient thermal resistance (R_θJA) of 52°C/W, per Section 5.4 of the datasheet. This value assumes standard JEDEC 2S2P board conditions and enables sustained 70 mA cathode current at +85°C ambient when mounted on a 1-in² copper pour.