Texas Instruments TLVH431CLPE3

Overview

TLVH431CLPE3 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, ±1.5% initial tolerance at 25°C, and operation down to 100 µA cathode current. It functions as a programmable Zener replacement or integrated-reference comparator in isolated flyback SMPS feedback loops, data converter references, and power-rail monitoring circuits.

For engineers reviewing the TLVH431CLPE3 datasheet, TLVH431CLPE3 pinout, TLVH431CLPE3 application, or TLVH431CLPE3 equivalent, key selection criteria include its 1.24 V minimum output voltage, 0.25 Ω dynamic impedance, –40°C to +125°C operating range, TO-92 package compatibility, and use in secondary-side regulation where low-voltage headroom and low leakage are critical.

Technical Context

The TLVH431CLPE3 implements a three-terminal shunt-regulator architecture with an internal 1.24 V bandgap reference and high-gain transconductance amplifier driving a Darlington sink output stage. Its open-loop mode enables comparator functionality with built-in reference; closed-loop operation with external resistive divider achieves precise voltage regulation from 1.24 V to 18 V.

It operates with cathode currents from 100 µA to 70 mA and maintains stable regulation without output capacitance due to internal compensation. The device exhibits 0.25 Ω typical dynamic impedance and <0.1 µA off-state cathode current, enabling high-accuracy, low-power voltage sensing and error amplification in isolated topologies.

Key Specifications

Pinout & Package

TLVH431CLPE3 uses the TO-92 (LP) package: 4.30 mm × 4.30 mm body, axial leaded, through-hole mount. Pin 1 = CATHODE, Pin 2 = ANODE, Pin 3 = REF.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431CLPE3, TLVH431AILP offers tighter 1% tolerance for improved system accuracy without layout changes, while TLVH431BCLP delivers 0.5% tolerance for metrology-critical designs - both retain identical thermal performance, cathode current capability, and TO-92 mechanical fit.

Availability

TLVH431CLPE3 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body electronics, and medical sensor modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TLVH431CLPE3 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 over 50 years of innovation in precision analog ICs.

The TLVH431 family was designed for low-voltage, high-accuracy shunt regulation in space-constrained and thermally demanding applications - particularly isolated power supplies and precision reference systems.

FAQ

What is the reference voltage tolerance of TLVH431CLPE3 at 25°C?

The TLVH431CLPE3 has a ±1.5% reference voltage tolerance at 25°C, corresponding to a 1.24 V nominal V_REF with a range of 1.221 V to 1.259 V. This grade is designated by the absence of an 'A' or 'B' suffix in the part number and is validated per TI's SLVS555N datasheet Section 5.5.

Can TLVH431CLPE3 operate with cathode currents below 100 µA?

No - TLVH431CLPE3 requires a minimum cathode current of 100 µA to maintain regulation and specified reference accuracy. Below this threshold, gain drops significantly, causing poor line/load regulation and increased V_REF deviation. The datasheet specifies IK(min) = 60 µA to 100 µA depending on temperature, with 100 µA as the guaranteed maximum at full range.

What package type does TLVH431CLPE3 use, and what are its key mechanical features?

TLVH431CLPE3 uses the TO-92 (LP) package: a 3-pin, axial-leaded, through-hole plastic case measuring 4.30 mm × 4.30 mm. Pins are arranged CATHODE–ANODE–REF (1–2–3), with standard JEDEC TO-92 lead spacing and soldering profile. It is RoHS-compliant and rated for reflow and wave-solder processes.

How does TLVH431CLPE3 differ from the TL431 in low-voltage applications?

TLVH431CLPE3 operates down to 1.24 V reference voltage and 100 µA cathode current, whereas the TL431 requires ≥2.5 V V_REF and ≥1 mA cathode current. This makes TLVH431CLPE3 suitable for 1.8 V–3.3 V systems where TL431 cannot regulate, and enables >90% reduction in bias power in always-on monitoring circuits.

Is an output capacitor required for stability with TLVH431CLPE3?

No - TLVH431CLPE3 is internally compensated and remains stable without an output capacitor between cathode and anode. External capacitors may be added for noise filtering or phase-margin tuning in high-capacitive-load scenarios, but are not required for basic regulation. Stability guidelines are provided in Figures 5-15 to 5-17 of the datasheet.