Texas Instruments TLV431IDBZRG4

Overview

TLV431IDBZRG4 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, ±1.5% initial tolerance at 25°C, 0.25 Ω typical dynamic impedance, 80 µA typical minimum cathode current, and operation from 1.24 V to 6 V output range. It serves as a Zener diode replacement or error amplifier in isolated flyback power supplies.

For engineers reviewing the TLV431IDBZRG4 datasheet, TLV431IDBZRG4 pinout, TLV431IDBZRG4 application, or TLV431IDBZRG4 equivalent, key selection considerations include its SOT-23-3 (DBZ) package, 1.5% reference tolerance, –40°C to 85°C industrial temperature range (TLV431I grade), ultra-low cathode current requirement, and compatibility with optocoupler-based secondary-side regulation circuits.

Technical Context

The TLV431IDBZRG4 implements a 3-terminal adjustable shunt reference architecture with an internal bandgap reference and NPN-based output stage. Its open-loop comparator mode enables voltage monitoring with integrated 1.24 V threshold, while closed-loop configuration with external resistors achieves precise voltage regulation down to 1.24 V.

It operates without external compensation due to internal frequency compensation, supports stable operation with capacitive loads up to 1 nF (per Figure 5-19–5-21), and maintains <11 mV reference deviation over –40°C to 85°C. The device's 0.25 Ω dynamic impedance ensures tight regulation under load transients.

Key Specifications

Pinout & Package

TLV431IDBZRG4 uses the SC-70-compatible SOT-23-3 (DBZ) package: 2.92 mm × 2.37 mm footprint, 1.45 mm height, surface-mount, lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431IDBZRG4, TLV431ACDBZR offers tighter reference accuracy at identical size and power, while TLVH431IDBVR extends voltage and current capability at the cost of larger footprint and non-interchangeable pinout-neither is pin-compatible, but both serve adjacent design needs in the same regulator family.

Availability

TLV431IDBZRG4 is available at Aetrix Electronics and suitable for isolated flyback SMPS regulation, voltage monitoring, and adjustable linear post-regulation requiring stable component supply, long-term lifecycle support, and industrial-grade temperature performance.

Supply support for TLV431IDBZRG4 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 ICs, with leadership in precision reference and power control technologies.

The TLV431x family was designed specifically for low-voltage, low-power shunt regulation and integrated reference applications in space-constrained industrial, computing, and telecom power systems-prioritizing small size, wide adjustability, and robust thermal stability.

FAQ

What is the reference voltage tolerance of TLV431IDBZRG4 at 25°C?

The TLV431IDBZRG4 has a ±1.5% reference voltage tolerance at 25°C, consistent with the base TLV431 grade (not A or B variants). This means its V_REF falls between 1.222 V and 1.258 V under nominal conditions, directly impacting absolute output accuracy in untrimmed designs.

Does TLV431IDBZRG4 require an output capacitor for stability?

No, TLV431IDBZRG4 is internally compensated and remains stable without an output capacitor between cathode and anode. However, if a capacitor is used for noise filtering or transient response shaping, Figure 5-19–5-21 in the datasheet provides phase margin guidance for values up to 1 nF.

What is the operating temperature range for TLV431IDBZRG4?

TLV431IDBZRG4 is rated for –40°C to +85°C, corresponding to the TLV431I industrial grade. This range is validated across all electrical parameters in the datasheet's Section 5.3 and supports deployment in automotive cabin, industrial PLC, and outdoor embedded equipment environments.

Can TLV431IDBZRG4 replace a standard Zener diode?

Yes, TLV431IDBZRG4 functions as a precision, adjustable Zener diode replacement. With 1.24 V reference, 0.25 Ω dynamic impedance, and sharp turn-on, it delivers superior regulation accuracy, lower leakage (<0.1 µA off-state), and programmable voltage vs. fixed-voltage Zeners-especially valuable below 3 V.

What package type does TLV431IDBZRG4 use?

TLV431IDBZRG4 uses the SOT-23-3 (DBZ) package: 2.92 mm × 2.37 mm footprint, 1.45 mm height, surface-mount, RoHS-compliant. This is distinct from SC-70-6 or SOT-89 variants and shares pinout compatibility with other TLV431x DBZ versions.