Texas Instruments TLVH431BCLPRE3

Overview

TLVH431BCLPRE3 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-to-anode voltage. It delivers stable regulation across –40°C to +125°C, supports cathode currents 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 TLVH431BCLPRE3 datasheet, TLVH431BCLPRE3 pinout, TLVH431BCLPRE3 application, or TLVH431BCLPRE3 equivalent, key selection criteria include its B-grade 0.5% initial VREF accuracy, ultra-low minimum cathode current (100 μA), wide 1.24–18 V adjustable output range, thermal stability over industrial and automotive temperature ranges, and compatibility with optocoupler-based secondary-side regulation circuits.

Technical Context

The TLVH431BCLPRE3 implements a precision bandgap reference and high-gain transconductance amplifier in a 3-terminal shunt topology. Its internal architecture forces the REF pin to 1.24 V relative to ANODE when sufficient cathode current (≥100 μA) flows, enabling closed-loop regulation via external resistor dividers.

It operates in two distinct functional modes: open-loop comparator mode (with integrated 1.24 V reference) and closed-loop shunt regulator mode. Unlike standard linear regulators, it requires no external compensation capacitor for stability due to internal frequency compensation, though capacitive load effects on phase margin are documented per Figure 5-15 through 5-17.

Key Specifications

Pinout & Package

TLVH431BCLPRE3 is supplied in the SOT-23-3 (DBZ) package with 2.92 mm × 1.30 mm body size and gull-wing leads. Pin 1 is CATHODE, Pin 2 is ANODE, Pin 3 is REF.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACLPE3, TLVH431BCLPRE3 delivers tighter reference accuracy critical for high-resolution measurement systems; compared with TLVH432BCLPRE3, it retains the standard TLVH431 pinout-avoiding layout changes while delivering identical regulation performance.

Availability

TLVH431BCLPRE3 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body electronics, and precision sensor signal conditioning requiring stable component supply and guaranteed long-term availability.

Supply support for TLVH431BCLPRE3 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, power management, and interface solutions.

The TLVH431 product line was designed for low-voltage, high-accuracy shunt regulation in space- and power-constrained applications-including isolated DC/DC converters, data converter references, and intelligent power monitoring systems.

FAQ

What is the reference voltage tolerance of TLVH431BCLPRE3 at 25°C?

The TLVH431BCLPRE3 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 B-grade specification is confirmed in Section 5.7 of the official TI datasheet SLVS555N. The tighter tolerance directly improves system-level accuracy in applications such as ADC references and voltage monitors, where TLVH431BCLPRE3 replaces less precise Zener diodes or lower-grade shunt regulators.

What is the minimum cathode current required for regulation in TLVH431BCLPRE3?

The minimum cathode current required for regulation in TLVH431BCLPRE3 is 100 μA, as specified in the "IK(min)" parameter under Electrical Characteristics (Section 5.5–5.7). This value is valid across the full operating temperature range and enables reliable startup and regulation in ultra-low-power applications-such as battery-backed supervisors or energy-harvesting systems-where legacy TL431 devices (1 mA min) would fail to regulate.

Which package type does TLVH431BCLPRE3 use, and what are its dimensions?

TLVH431BCLPRE3 uses the SOT-23-3 (DBZ) package with nominal body dimensions of 2.92 mm × 1.30 mm. This 3-pin gull-wing surface-mount package is explicitly listed in TI's orderable addendum and mechanical drawings for the TLVH431BxxDBZ variant. Its compact footprint supports high-density PCB layouts in portable and automotive ECUs, and its thermal resistance (R_θJA = 206°C/W) is validated for operation up to +125°C ambient.

Can TLVH431BCLPRE3 be used without an output capacitor?

Yes, TLVH431BCLPRE3 is internally compensated and stable without an output capacitor between CATHODE and ANODE, as stated in Section 7.3 of the datasheet. This eliminates the need for external stabilization components in most applications. However, if a capacitive load is present, Figures 5-15 to 5-17 provide phase-margin guidance to select appropriate capacitance values-ensuring stability in noise-sensitive or dynamically loaded systems where TLVH431BCLPRE3 serves as a reference or error amplifier.

How does TLVH431BCLPRE3 differ from TLVH432BCLPRE3?

TLVH431BCLPRE3 and TLVH432BCLPRE3 share identical electrical specifications-including 0.5% V_REF tolerance, 100 μA I_K(min), and –40°C to +125°C operation-but differ exclusively in pinout. TLVH431BCLPRE3 uses CATHODE–ANODE–REF (Pin 1–2–3), while TLVH432BCLPRE3 uses REF–CATHODE–ANODE. This difference is documented in Figures 4-4 and 4-5 of the datasheet. TLVH431BCLPRE3 maintains backward compatibility with standard TLVH431 layouts, avoiding PCB redesign.