Texas Instruments TLVH431BCDBVR

Overview

TLVH431BCDBVR from Texas Instruments is a precision adjustable shunt voltage reference IC with 0.5% initial reference voltage tolerance at 25°C, 1.24 V nominal reference voltage, and operation down to 1.24 V cathode-to-anode voltage. It delivers stable regulation across –40°C to +125°C, supports 100 μA to 70 mA cathode current, and features 0.25 Ω typical dynamic impedance - enabling use as a low-leakage Zener replacement or error amplifier in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH431BCDBVR datasheet, TLVH431BCDBVR pinout, TLVH431BCDBVR application, or TLVH431BCDBVR equivalent, key selection criteria include its B-grade accuracy, SC-70-6 package footprint, ultra-low minimum cathode current, thermal stability over automotive temperature range, and compatibility with optocoupler-based secondary-side regulation circuits.

Technical Context

The TLVH431BCDBVR 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 regulator mode. Its functional block includes a high-gain transconductance amplifier comparing REF pin voltage against an internal reference, driving a sink current through the CATHODE terminal.

It requires ≥100 μA cathode current to enter linear regulation, exhibits <0.5 μA reference input current, and maintains <12 mV VREF deviation over –40°C to +125°C (Q-grade). The device is internally compensated and stable without external capacitance, though phase margin vs. capacitive load is characterized up to 100 nF.

Key Specifications

Pinout & Package

TLVH431BCDBVR is packaged in a 6-pin SC-70 (DCK) package measuring 2.00 mm × 1.25 mm, offering 40% smaller footprint than SOT-23-3. Pin 1 is CATHODE, Pin 2 is ANODE, Pin 3 is REF, Pin 4 and Pin 5 are NC (no internal connection), and Pin 6 is substrate-connected - must be tied to ANODE or left floating per datasheet guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVR, TLVH431BCDBVR delivers tighter initial accuracy critical for high-resolution sensing; compared with TLVH432BIDBV, it offers 40% smaller footprint and lower thermal resistance (259°C/W vs. 206°C/W) but requires managing two NC pins and substrate connection.

Availability

TLVH431BCDBVR is available at Aetrix Electronics and suitable for automotive power management, industrial sensor interfaces, and isolated DC-DC converter designs requiring stable component supply with guaranteed long-term availability.

Supply support for TLVH431BCDBVR 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 decades of expertise in precision reference design.

The TLVH431 family was engineered to replace TL431 in low-voltage systems, targeting isolated power supplies, data acquisition front-ends, and voltage supervision circuits demanding sub-2 V operation and automotive-grade reliability.

FAQ

What is the reference voltage tolerance of TLVH431BCDBVR at 25°C?

The TLVH431BCDBVR has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal VREF with min/max values of 1.234 V and 1.246 V. This B-grade accuracy is confirmed in Section 5.7 of the TI SLVS555N datasheet and applies specifically to the TLVH431BCDBVR variant in SC-70 packaging.

Can TLVH431BCDBVR operate with cathode voltage below 2.5 V?

Yes - TLVH431BCDBVR is explicitly designed for low-voltage operation starting at 1.24 V cathode-to-anode voltage, unlike the TL431 which requires ≥2.5 V. This enables direct use in 1.8 V and 2.5 V systems, as verified in the "Low-voltage operation" feature list and Figure 6-1 test circuit in the TLVH431BCDBVR datasheet.

What is the correct handling of Pin 6 (substrate) on TLVH431BCDBVR?

Pin 6 on TLVH431BCDBVR is the substrate connection and must be connected to the ANODE (Pin 2) or left unconnected - it must never be tied to a different potential. This requirement is specified in the Pin Functions table and Figure 4-2 of the TI datasheet to prevent latch-up and ensure thermal stability.

Does TLVH431BCDBVR require an output capacitor for stability?

No - TLVH431BCDBVR is internally compensated and remains stable without an output capacitor between CATHODE and ANODE. However, if a capacitor is added for noise filtering, Figures 5-15 to 5-17 in the datasheet provide phase margin vs. capacitive load curves to guide selection up to 100 nF.

How does TLVH431BCDBVR differ from TLVH432B variants?

TLVH431BCDBVR and TLVH432B share identical electrical specifications including 0.5% VREF tolerance and –40°C to +125°C operation, but differ in pinout and package: TLVH431BCDBVR uses 6-pin SC-70 with CATHODE–ANODE–REF–NC–NC–SUBSTRATE arrangement, while TLVH432B variants use 3-pin SOT-23 or SOT-89 with CATHODE–REF–ANODE ordering - not pin-compatible.