Texas Instruments TLVH431BQDBVRE4

Overview

TLVH431BQDBVRE4 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 0.5% reference voltage tolerance at 25°C, 1.24 V nominal reference voltage, and operation down to 1.24 V cathode-anode voltage. It delivers stable regulation across –40°C to +125°C, supports cathode current from 100 μA to 70 mA, and features 0.25 Ω typical dynamic impedance - enabling use as a Zener replacement or error amplifier in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH431BQDBVRE4 datasheet, TLVH431BQDBVRE4 pinout, TLVH431BQDBVRE4 application, or TLVH431BQDBVRE4 equivalent, key selection considerations include its B-grade accuracy, SOT-23-5 package pin configuration, ultra-low minimum cathode current requirement, thermal stability over automotive temperature range, and compatibility with optocoupler-based secondary-side regulation circuits.

Technical Context

The TLVH431BQDBVRE4 implements a bandgap-referenced error amplifier with internal 1.24 V reference and Darlington output stage, operating in either open-loop comparator mode or closed-loop shunt regulation mode. Its functional block includes a high-gain transconductance amplifier comparing REF pin voltage to an internal reference, driving a sink current at the CATHODE terminal.

Unlike the TL431, it achieves regulation with only 100 μA minimum cathode current and operates from as low as 1.24 V, making it suitable for 3.3 V and lower-output isolated power supplies. The device is internally compensated and stable without external output capacitance, though phase margin vs. capacitive load is characterized up to 10 nF.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 5-pin surface-mount with exposed pad not electrically connected. Pin 2 is substrate-connected and must be tied to ANODE or left floating per TI specification.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BQDBVRE4, TLVH431BQDBZR offers identical regulation performance in a smaller 3-pin footprint but demands pinout-aware layout revision, while TLVH432BQPK provides superior thermal handling in a larger package - making the DBV variant optimal for space-constrained, moderate-power automotive and industrial feedback designs.

Availability

TLVH431BQDBVRE4 is available at Aetrix Electronics and suitable for automotive power management, industrial sensor signal conditioning, and isolated DC/DC converter feedback requiring stable component supply across extended temperature ranges.

Supply support for TLVH431BQDBVRE4 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 TLVH431 family was designed for low-voltage, high-accuracy shunt regulation in space- and power-constrained systems - targeting automotive, industrial, and telecom applications needing stable references below 2.5 V.

FAQ

What is the reference voltage tolerance of TLVH431BQDBVRE4 at 25°C?

The TLVH431BQDBVRE4 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 specified in Section 5.7 of the TI datasheet and applies across all operating conditions unless otherwise noted.

Can TLVH431BQDBVRE4 operate with a cathode-to-anode voltage below 2.5 V?

Yes, TLVH431BQDBVRE4 is specifically designed for low-voltage operation starting at 1.24 V cathode-to-anode voltage. Unlike the TL431, it regulates stably down to this minimum headroom, enabling use in 1.8 V, 2.5 V, and 3.3 V systems - confirmed by TI's recommended operating conditions (V_KA ≥ V_REF).

What is the minimum cathode current required for regulation in TLVH431BQDBVRE4?

The TLVH431BQDBVRE4 requires a minimum cathode current of 100 μA to maintain regulation, as specified in the IK(min) parameter (Section 5.5–5.7). This value is guaranteed over the full –40°C to +125°C temperature range and is significantly lower than the 1 mA required by TL431 devices.

Does TLVH431BQDBVRE4 require an external output capacitor for stability?

No, TLVH431BQDBVRE4 is internally compensated and stable without an external capacitor between CATHODE and ANODE. TI confirms this in Section 7.3, though Figure 5-15 through 5-17 provide guidance for optional capacitive load stabilization if needed for specific noise or transient requirements.

How does the SOT-23-5 pinout of TLVH431BQDBVRE4 differ from TLVH431BQDBZR?

TLVH431BQDBVRE4 uses a 5-pin SOT-23 (DBV) with pins: 1=NC, 2=Substrate, 3=CATHODE, 4=REF, 5=ANODE. TLVH431BQDBZR uses 3-pin SOT-23 (DBZ) with pins: 1=REF, 2=CATHODE, 3=ANODE - no NC or substrate pins. The pin functions and electrical behavior are identical, but physical layout and routing must be redesigned.