Texas Instruments TLVH432AIPK

Overview

TLVH432AIPK from Texas Instruments is a low-voltage adjustable precision shunt regulator in SOT-89-3 package, providing 1.24 V reference voltage with ±1% tolerance at 25°C, 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 TLVH432AIPK datasheet, TLVH432AIPK pinout, TLVH432AIPK application, or TLVH432AIPK equivalent, key selection criteria include reference accuracy over temperature, minimum cathode current for regulation, dynamic impedance, cathode voltage headroom down to 1.24 V, and SOT-89 thermal performance (R_θJA = 52°C/W).

Technical Context

The TLVH432AIPK implements a three-terminal shunt-regulator architecture with internal 1.24 V bandgap reference and high-gain transconductance amplifier driving a Darlington output stage. Its open-loop mode enables comparator functionality with built-in reference; closed-loop operation with external resistive divider achieves adjustable output voltage from 1.24 V to 18 V.

Unlike the TLVH431, the TLVH432AIPK uses reversed pinout in SOT-89: Pin 1 = CATHODE, Pin 2 = ANODE, Pin 3 = REF - enabling direct compatibility with optocoupler-based feedback networks where cathode connects to phototransistor collector and anode ties to ground-referenced bias.

Key Specifications

Pinout & Package

SOT-89-3 package: 4.50 mm × 2.50 mm body, 1.0 mm nominal height, gull-wing leads, thermally enhanced tab (anode-connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH432AIPK, TLVH431AIPK requires PCB redesign due to inverted pinout but offers identical regulation performance, while TLVH432ACPK delivers higher initial accuracy at no thermal or footprint penalty - making it suitable for applications where reference drift dominates overall error.

Availability

TLVH432AIPK is available at Aetrix Electronics and suitable for isolated SMPS design, precision voltage monitoring, and low-power reference applications requiring stable component supply across automotive, industrial, and telecom end equipment.

Supply support for TLVH432AIPK 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 power management, signal chain, and high-reliability components.

The TLVH432 product line targets low-voltage, high-accuracy shunt regulation in space- and power-constrained systems - specifically engineered for secondary-side feedback in isolated DC/DC converters and precision voltage supervision.

FAQ

What is the exact pinout configuration of TLVH432AIPK in the SOT-89 package?

The TLVH432AIPK uses a reversed SOT-89 pinout: Pin 1 is CATHODE, Pin 2 is ANODE (tab-connected), and Pin 3 is REF. This differs from TLVH431 variants and aligns with common optocoupler feedback layouts where cathode drives the phototransistor collector. Always verify against Figure 4-7 in the SLVS555N datasheet.

Does TLVH432AIPK require an output capacitor for stability?

No, TLVH432AIPK is internally compensated and remains stable without an output capacitor between cathode and anode. However, if a capacitor is added for noise filtering or transient response shaping, Figures 5-15 through 5-17 in the datasheet provide phase-margin guidance for capacitive loads up to 10 nF at various cathode voltages.

What is the minimum cathode current needed for regulation in TLVH432AIPK?

The TLVH432AIPK requires a minimum cathode current of 100 μA to maintain regulation across its full operating temperature range (–40°C to +125°C). At 25°C, regulation is guaranteed down to 60 μA, but design margin must account for worst-case temperature drift per Section 5.5 of the datasheet.

Can TLVH432AIPK be used as a comparator, and what are its key limitations?

Yes, TLVH432AIPK operates as a comparator in open-loop mode with integrated 1.24 V reference. Key limitations include mandatory cathode current ≥100 μA for sufficient gain, inability to drive heavy capacitive loads directly, and absence of rail-to-rail output - output swings between anode and cathode rails, not supply rails.

How does the thermal performance of TLVH432AIPK compare to other packages in the TLVH432 family?

TLVH432AIPK in SOT-89 achieves R_θJA = 52°C/W, significantly better than SC70 (259°C/W) and comparable SOT-23 variants (206°C/W). This allows >1.2 W continuous power dissipation at +85°C ambient - critical for high-current shunt regulation in compact power supplies where thermal headroom is limited.