Texas Instruments TLV431BIDBVTG4

Overview

TLV431BIDBVTG4 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 0.5% initial reference voltage tolerance at 25°C, 1.24 V nominal reference voltage, and operation down to 1.24 V cathode-anode voltage. It delivers 0.25 Ω typical dynamic impedance, 80 µA typical minimum cathode current for regulation, and supports output voltage adjustment from 1.24 V to 6 V using two external resistors. It is used in isolated flyback secondary-side regulation for 3.3 V SMPS designs.

For engineers reviewing the TLV431BIDBVTG4 datasheet, TLV431BIDBVTG4 pinout, TLV431BIDBVTG4 application, or TLV431BIDBVTG4 equivalent, key selection considerations include reference accuracy over temperature (±6 mV from –40°C to 85°C), ultra-small SC-70 package footprint, open-loop comparator functionality with integrated reference, and compatibility with optocoupler-based feedback loops in low-voltage power supplies.

Technical Context

The TLV431BIDBVTG4 implements a precision bandgap reference and high-gain NPN-based error amplifier in a 3-terminal shunt topology. Its internal architecture enables stable closed-loop regulation without external compensation capacitors and supports both open-loop comparator mode and closed-loop shunt regulation modes.

In closed-loop configuration, it sinks cathode current proportional to the difference between the REF pin voltage and its internal 1.24 V reference, enabling precise voltage or current regulation. In open-loop mode, it functions as a comparator with built-in reference, requiring ≥55 µA cathode current to maintain sufficient gain for fast response.

Key Specifications

Pinout & Package

TLV431BIDBVTG4 is housed in a 6-pin SC-70 (DCK) package measuring 2.0 mm × 1.5 mm - 40% smaller than SOT-23-3 - with thermal resistance R_θJA = 87°C/W. The package is surface-mount, lead-free, and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431BIDBZR and TLVH431IDBVR, the TLV431BIDBVTG4 offers the smallest PCB footprint (SC-70), highest reference accuracy (0.5%), and lowest thermal resistance among DCK-packaged variants - making it optimal for miniaturized, high-precision power management where space and accuracy are critical.

Availability

TLV431BIDBVTG4 is available at Aetrix Electronics and suitable for isolated flyback converters, voltage monitoring systems, and programmable current sinks requiring stable component supply, tight reference accuracy, and ultra-compact packaging.

Supply support for TLV431BIDBVTG4 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 TLV431 family was designed specifically for low-voltage, high-accuracy shunt regulation in space-constrained power systems - targeting 3.3 V and lower SMPS, battery management, and intelligent sensing applications where traditional TL431 devices cannot operate.

FAQ

What is the reference voltage tolerance of TLV431BIDBVTG4 at 25°C?

The TLV431BIDBVTG4 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal reference with a range of 1.234 V to 1.246 V. This tighter tolerance distinguishes it from the TLV431A (±1%) and base TLV431 (±1.5%) variants, making TLV431BIDBVTG4 suitable for high-accuracy regulation tasks where minimal initial error is critical.

Can TLV431BIDBVTG4 be used as a comparator?

Yes, TLV431BIDBVTG4 can operate in open-loop comparator mode with integrated reference. When supplied with ≥55 µA cathode current, it compares the voltage at the REF pin to its internal 1.24 V reference and drives the CATHODE pin low if the REF voltage exceeds that threshold. This eliminates the need for a separate reference IC in threshold-detection circuits, and TLV431BIDBVTG4's sharp turn-on characteristic ensures reliable switching behavior.

What is the minimum cathode current required for regulation in TLV431BIDBVTG4?

The TLV431BIDBVTG4 requires a minimum cathode current of 55 µA to enter and maintain regulation mode, as specified in its electrical characteristics table for the BI grade (–40°C to 85°C). This low IK(min) enables efficient operation in low-power and standby applications, and is significantly lower than the 1 mA required by legacy TL431 devices - a key advantage for energy-sensitive designs.

Does TLV431BIDBVTG4 require an output capacitor for stability?

No, TLV431BIDBVTG4 is internally compensated and remains stable without an output capacitor between CATHODE and ANODE. This simplifies design and reduces component count in feedback loops. However, if an output capacitor is added for noise filtering or transient response shaping, stability must be verified using the phase margin vs. capacitive load curves in the datasheet (Figures 5-19 to 5-21), especially for loads >1 nF.

What package type is used for TLV431BIDBVTG4 and how does it compare to SOT-23-3?

TLV431BIDBVTG4 uses the SC-70 (DCK) package - a 6-pin surface-mount outline measuring 2.0 mm × 1.5 mm. It is 40% smaller in footprint than the standard SOT-23-3 package (2.92 mm × 2.37 mm) and provides better thermal performance (R_θJA = 87°C/W vs ~206°C/W for SOT-23-3). Though pin-compatible in function (CATHODE/REF/ANODE on Pins 1/3/6), the SC-70 requires distinct land patterns and reflow profiles due to its finer pitch and smaller size.