Texas Instruments TLVH431BIDCKRE4

Overview

TLVH431BIDCKRE4 from Texas Instruments is a low-voltage adjustable precision shunt regulator in SC-70-6 package, featuring 0.5% reference voltage tolerance at 25°C, 1.24 V nominal reference voltage, 100 μA to 70 mA cathode current range, and operation from –40°C to +125°C. It serves as an error amplifier or voltage reference in isolated flyback SMPS feedback loops for 3.3 V systems.

For engineers reviewing the TLVH431BIDCKRE4 datasheet, TLVH431BIDCKRE4 pinout, TLVH431BIDCKRE4 application, or TLVH431BIDCKRE4 equivalent, key selection criteria include reference accuracy, cathode current headroom, thermal stability across automotive temperature range, SC-70 footprint constraints, and compatibility with optocoupler-based secondary-side regulation topologies.

Technical Context

The TLVH431BIDCKRE4 implements a bandgap-referenced error amplifier with internal 1.24 V reference and Darlington output stage, enabling precise shunt regulation down to 1.24 V. Its open-loop comparator mode supports voltage monitoring without external reference, while closed-loop configuration with resistive divider achieves adjustable output from VREF to 18 V.

It operates with ultra-low minimum cathode current (100 μA), exhibits 0.25 Ω typical dynamic impedance, and maintains stable performance under capacitive loads up to 10 nF-verified via phase margin testing at 1.25 V, 2.5 V, and 5 V cathode voltages.

Key Specifications

Pinout & Package

TLVH431BIDCKRE4 uses the 6-pin SC-70 package (DCK suffix), with pin 1 = CATHODE, pin 2 = ANODE, pin 3 = REF, pin 4 = NC, pin 5 = NC, pin 6 = substrate connection (must be tied to ANODE or left open). The compact 2.00 mm × 1.25 mm body enables high-density layout in power management ICs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BIDCKRE4, TLVH431BIDBVR offers identical performance in a larger SMT package with higher thermal resistance, while TLVH431BQDBZR provides the same regulation capability in through-hole form-neither is pin-compatible, but both satisfy functional requirements in alternate mechanical contexts.

Availability

TLVH431BIDCKRE4 is available at Aetrix Electronics and suitable for isolated flyback SMPS design, precision ADC reference circuits, and automotive-grade voltage monitoring applications requiring stable component supply and long-term lifecycle support.

Supply support for TLVH431BIDCKRE4 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, embedded processing, and power management technologies, with leadership in precision analog ICs since 1930.

The TLVH431 family was designed for low-voltage, high-accuracy shunt regulation in space-constrained and thermally demanding applications-including isolated power supplies, data acquisition systems, and automotive subsystems.

FAQ

What is the reference voltage tolerance of TLVH431BIDCKRE4 at 25°C?

The TLVH431BIDCKRE4 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a V_REF range of 1.234 V to 1.246 V. This grade-B accuracy is specified in Section 5.7 of the TI datasheet SLVS555N and applies to the exact part number TLVH431BIDCKRE4 in its SC-70 package. The tolerance remains stable across cathode currents from 100 μA to 70 mA.

Can TLVH431BIDCKRE4 replace a standard Zener diode in low-leakage applications?

Yes, TLVH431BIDCKRE4 can directly replace low-voltage Zener diodes (e.g., 1.2 V or 1.5 V types) due to its 0.25 Ω dynamic impedance, 0.1 μA typical off-state cathode current at 18 V, and sharp turn-on characteristic. Unlike Zeners, TLVH431BIDCKRE4 provides guaranteed 0.5% initial accuracy and superior temperature stability-making it ideal for precision biasing and voltage clamping where leakage and drift matter.

What is the minimum cathode current required for regulation in TLVH431BIDCKRE4?

The minimum cathode current required for regulation in TLVH431BIDCKRE4 is 100 μA, verified across –40°C to +125°C per Section 5.7 of the datasheet. Below this level, gain drops significantly and regulation becomes unreliable. This value is lower than TL431's 1 mA requirement, enabling TLVH431BIDCKRE4 to operate efficiently in ultra-low-power monitoring circuits where supply current is tightly constrained.

Does TLVH431BIDCKRE4 require an output capacitor for stability?

No, TLVH431BIDCKRE4 is internally compensated and stable without an output capacitor between cathode and anode. This eliminates mandatory bypass components in most shunt regulator configurations. However, if an output capacitor is used for noise filtering or transient suppression, Figures 5-15 to 5-17 in the datasheet provide phase-margin guidance for capacitive loads up to 10 nF at various cathode voltages.

How does the SC-70 package of TLVH431BIDCKRE4 affect thermal performance?

The SC-70-6 package of TLVH431BIDCKRE4 has a junction-to-ambient thermal resistance (R_θJA) of 259°C/W, higher than SOT-23-5 (206°C/W) or TO-92 (140°C/W). This means power dissipation capability is reduced-maximum continuous cathode current should be limited to ~35 mA at +85°C ambient to keep junction temperature below 125°C. Layout best practices include maximizing copper area on ANODE pad and avoiding thermal isolation.