Texas Instruments TLVH431BQDCKT

Overview

TLVH431BQDCKT from Texas Instruments is a low-voltage adjustable precision shunt regulator in SC-70 package, providing 1.24 V reference voltage with ±0.5% initial tolerance at 25°C, 100 μA minimum cathode current for regulation, 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 TLVH431BQDCKT datasheet, TLVH431BQDCKT pinout, TLVH431BQDCKT application, or TLVH431BQDCKT equivalent, key selection criteria include reference accuracy over temperature, dynamic impedance (0.25 Ω), cathode current range (100 μA–70 mA), and SC-70 footprint compatibility in space-constrained power management designs.

Technical Context

The TLVH431BQDCKT implements a precision bandgap reference and high-gain transconductance amplifier in a 3-terminal shunt topology. Its internal architecture enables closed-loop regulation via external resistor divider feedback from cathode to reference pin, or open-loop comparator operation with integrated 1.24 V threshold.

It operates down to 1.24 V cathode-anode voltage, supports output voltage adjustment from V_REF to 18 V, and maintains stable regulation across industrial and automotive temperature ranges (–40°C to +125°C) with typical 0.25 Ω dynamic impedance and <0.5 μA reference input current.

Key Specifications

Pinout & Package

TLVH431BQDCKT uses the SC-70 (DCK) 6-pin package (2.00 mm × 1.25 mm), with pins 1 (CATHODE), 2 (ANODE), 3 (REF), and NC/substrate connections on pins 4, 5, and 6 per TI's official pinout diagram (Figure 4-2).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BQDCKT, TLVH431BIDCKR trades automotive temperature range for lower cost, while TLVH432BQDCKT provides identical performance but mandates board-level pinout changes - making TLVH431BQDCKT the optimal choice for new Q-grade designs requiring direct SC-70 compatibility.

Availability

TLVH431BQDCKT is available at Aetrix Electronics and suitable for automotive power management, isolated DC/DC converters, and precision analog monitoring requiring stable component supply across extended temperature ranges.

Supply support for TLVH431BQDCKT 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 focused on analog and embedded processing technologies, with decades of expertise in precision analog ICs and power management solutions.

The TLVH431 family was designed specifically for low-voltage shunt regulation in isolated power supplies and precision reference applications, targeting automotive, industrial, and telecom systems demanding high accuracy and wide temperature operation.

FAQ

What is the reference voltage tolerance of TLVH431BQDCKT at 25°C?

The TLVH431BQDCKT has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a nominal 1.24 V output with a guaranteed range of 1.234 V to 1.246 V. This B-grade accuracy is specified in Section 5.7 of the TI datasheet and applies across all operating conditions at room temperature. TLVH431BQDCKT maintains this precision as part of its Q-grade qualification for automotive applications.

Does TLVH431BQDCKT require an output capacitor for stability?

No, TLVH431BQDCKT is internally compensated and remains stable without an output capacitor between cathode and anode. This eliminates external compensation components and simplifies layout. However, if a capacitor is added for noise filtering or transient response, Figures 5-15 through 5-17 in the TI datasheet provide phase-margin guidance for capacitive loads up to 100 nF. TLVH431BQDCKT's inherent stability is a key design advantage over discrete op-amp + reference solutions.

What is the minimum cathode current needed for regulation in TLVH431BQDCKT?

The minimum cathode current required for regulation in TLVH431BQDCKT is 100 μA, as specified in the "IK(min)" parameter under Section 5.5–5.7 of the TI datasheet. This value holds across the full –40°C to +125°C temperature range. Supplying less than 100 μA may result in insufficient gain and unstable regulation. TLVH431BQDCKT's low IK(min) enables efficient operation in ultra-low-power applications where TL431 (1 mA min) would fail.

How does TLVH431BQDCKT differ from TLVH432BQDCKT?

TLVH431BQDCKT and TLVH432BQDCKT share identical electrical specifications, temperature rating (–40°C to +125°C), and SC-70 package, but differ in pinout: TLVH431BQDCKT uses CATHODE/ANODE/REF on pins 1/2/3, while TLVH432BQDCKT uses REF/ANODE/CATHODE. This reversal means TLVH432BQDCKT is not pin-compatible with TLVH431BQDCKT and requires PCB layout changes. TLVH431BQDCKT is the correct choice for designs referencing the standard TLVH431 pin configuration.

Can TLVH431BQDCKT be used as a comparator?

Yes, TLVH431BQDCKT can operate as a comparator with integrated 1.24 V reference in open-loop mode. When cathode current ≥100 μA is supplied and no feedback is applied from cathode to REF, the device exhibits high open-loop gain and sharp turn-on behavior. It compares the voltage at the REF pin to its internal reference and sinks cathode current accordingly - enabling simple voltage monitoring or threshold detection without external components. TLVH431BQDCKT's low I_ref (0.1–0.5 μA) minimizes sensing network errors in such applications.