Texas Instruments TLV431BIDBVR

Overview

TLV431BIDBVR 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 - widely used in isolated flyback secondary-side regulation and low-voltage Zener replacement.

For engineers reviewing the TLV431BIDBVR datasheet, TLV431BIDBVR pinout, TLV431BIDBVR application, or TLV431BIDBVR equivalent, this page provides verified technical context, package-specific pin functions, real-world design implications of its 0.5% VREF tolerance and SC-70 footprint, and validated alternative options for voltage reference and error amplifier roles in power management circuits.

Technical Context

The TLV431BIDBVR implements a three-terminal shunt regulator architecture with an internal bandgap reference and high-gain NPN-based error amplifier driving a Darlington sink output stage. Its open-loop comparator mode enables precise voltage monitoring without external feedback, while closed-loop configuration with resistive divider feedback achieves stable voltage regulation across 1.24 V–6 V.

It operates with cathode-anode voltage (VKA) ≥ 1.24 V and requires ≥ 55 µA cathode current for regulation over full temperature range. The device is internally compensated and stable without an output capacitor, though capacitive load stability depends on VKA and is characterized up to 10 nF per TI's phase margin vs. load curves.

Key Specifications

Pinout & Package

TLV431BIDBVR is packaged in the ultra-small SC-70 (DCK) 6-pin package with 0.65 mm pitch. Pin 1 is CATHODE, Pin 3 is REF, Pin 6 is ANODE; Pins 2, 4, and 5 are NC (no internal connection). Substrate connection (Pin 2) must be tied to ANODE or left floating per TI specification.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431ACDBVR, TLV431BIDBVR provides tighter reference accuracy for high-precision feedback loops, while TLVH431IDBVR trades package compatibility for extended voltage and current capability - making TLV431BIDBVR optimal for compact, accuracy-critical 1.24–6 V shunt regulation.

Availability

TLV431BIDBVR is available at Aetrix Electronics and suitable for isolated flyback converters, precision voltage monitors, low-power Zener replacements, and adjustable current sinks requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TLV431BIDBVR 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 delivering analog and embedded processing solutions, with leadership in precision analog, power management, and signal chain technologies.

The TLV431BIDBVR belongs to TI's precision shunt reference product line, designed specifically for low-voltage, high-accuracy regulation and error amplification in space-constrained and energy-efficient power systems.

FAQ

What is the reference voltage tolerance of TLV431BIDBVR at 25°C?

The TLV431BIDBVR has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a VREF range of 1.234 V to 1.246 V. This tight tolerance is specified in Section 5.7 of the TI datasheet SLVS139Z and directly enables high-accuracy output regulation in feedback loops without trimming. TLV431BIDBVR maintains this grade across its SC-70 (DCK) packaging variant.

Can TLV431BIDBVR replace a standard Zener diode in a 3.3 V rail clamp?

Yes, TLV431BIDBVR can directly replace a 3.3 V Zener diode in rail clamping applications. When configured with R1 and R2 to set VO = 3.3 V, it delivers 0.25 Ω dynamic impedance versus ~20 Ω for typical Zeners - reducing voltage deviation under load transients by >95%. Its 0.5% VREF tolerance also ensures far tighter clamping accuracy than discrete Zeners, which commonly exhibit ±5% tolerance and strong temperature dependence.

What is the minimum cathode current required for regulation in TLV431BIDBVR?

The TLV431BIDBVR requires a minimum cathode current (IK(min)) of 55 µA to maintain regulation across its full operating temperature range (–40°C to 125°C). At 25°C, regulation is guaranteed down to 55 µA, rising to 100 µA at 125°C per Section 5.7 of the datasheet. This ultra-low requirement enables use in micropower designs where TL431 (1 mA IK(min)) would be unsuitable.

Does TLV431BIDBVR require an output capacitor for stability?

No, TLV431BIDBVR is internally compensated and stable without an output capacitor between CATHODE and ANODE in most configurations. TI's datasheet confirms stability up to 10 nF capacitive load depending on VKA, with phase margin curves provided in Figures 5-19 through 5-21. Adding a capacitor is optional and only recommended when specific noise filtering or transient suppression is required - no compensation network redesign is needed.

What is the function of Pin 2 in the TLV431BIDBVR SC-70 package?

Pin 2 of the TLV431BIDBVR in SC-70 (DCK) package is the substrate connection, labeled "*" in TI's pinout diagrams. Per Section 4 of the datasheet, it must be connected to ANODE (Pin 6) or left unconnected - it must never be tied to any other potential. This connection stabilizes the internal die potential and prevents latch-up; leaving it floating is permitted but tying to ANODE is preferred for robustness in noisy environments.