Texas Instruments TLV431IDBVT

Overview

TLV431IDBVT from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, ±1% initial tolerance at 25°C, and operation from 1.24 V to 6 V output range. It delivers 0.25 Ω typical dynamic impedance, 80 µA typical minimum cathode current, and supports secondary-side regulation in isolated flyback SMPSs.

For engineers reviewing the TLV431IDBVT datasheet, TLV431IDBVT pinout, TLV431IDBVT application, or TLV431IDBVT equivalent, this page provides verified pin functions, thermal performance data (R_θJA = 206°C/W), temperature-stable reference behavior (±6 mV over –40°C to 85°C), and real-world design guidance for Zener replacement and comparator use.

Technical Context

The TLV431IDBVT operates as a 3-terminal adjustable shunt reference with internal bandgap reference and NPN-based error amplifier driving a Darlington sink output stage. Its open-loop gain enables precise comparator operation with integrated 1.24 V threshold, while closed-loop configuration with external resistors achieves stable voltage regulation down to 1.24 V.

It requires ≥55 µA cathode current to enter regulation, exhibits <0.1 µA off-state leakage at 6 V, and maintains stability without output capacitance-though phase margin vs. capacitive load is characterized up to 1 nF for design validation in feedback loops.

Key Specifications

Pinout & Package

TLV431IDBVT uses the SC-70 (DCK) 6-pin package with exposed substrate connection. Pin 2 (substrate) must be connected to ANODE or left floating per TI specification. The device has no internal connection on pins 4 and 5.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431IDBVT, TLV431ACDBVR offers identical performance in commercial environments but lacks extended temperature qualification, while TLVH431IDBVR expands voltage/current capability at the cost of pin compatibility and board layout change.

Availability

TLV431IDBVT is available at Aetrix Electronics and suitable for isolated power supplies, voltage monitoring systems, and low-voltage Zener replacement circuits requiring stable component supply and guaranteed long-term sourcing.

Supply support for TLV431IDBVT 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 leader delivering analog and embedded processing solutions, with over 90 years of innovation in precision analog ICs and power management.

The TLV431IDBVT belongs to TI's precision shunt reference product line, designed specifically for low-voltage, high-accuracy regulation and comparator applications in space-constrained and thermally demanding industrial and computing systems.

FAQ

What is the maximum cathode-anode voltage for TLV431IDBVT?

The absolute maximum cathode voltage (V_KA) for TLV431IDBVT is 7 V relative to the anode terminal. Operating beyond this risks permanent damage. The recommended operating range is 1.24 V to 6 V, aligning with its adjustable output specification. This limit is defined in Section 5.1 of the TI SLVS139Z datasheet and applies regardless of temperature or current conditions.

Does TLV431IDBVT require an output capacitor for stability?

No, TLV431IDBVT is internally compensated and remains stable without an output capacitor between cathode and anode. However, if a capacitive load is added-such as for noise filtering-the phase margin must be verified using Figure 5-19 through Figure 5-21 in the datasheet. Capacitors above ~300 pF may reduce phase margin below 45° depending on V_KA, so empirical validation is recommended for each design.

What is the function of Pin 2 on TLV431IDBVT?

Pin 2 on TLV431IDBVT is the substrate connection, not an electrical signal pin. Per TI's Pin Functions table (Section 4), it must either be connected to the ANODE terminal or left unconnected (floating). It is not internally wired to any circuitry and serves only mechanical die attachment; incorrect connection-such as tying it to a different potential-may cause parametric shifts or reliability issues.

Can TLV431IDBVT replace TL431 in existing designs?

TLV431IDBVT can replace TL431 only in designs where the lower 1.24 V reference and reduced voltage headroom are acceptable-and only if the SC-70 (DCK) package and 6-pin layout are accommodated. TL431 uses 2.5 V reference and requires ≥2.5 V cathode-anode differential; TLV431IDBVT's 1.24 V reference and 55–80 µA minimum cathode current enable new low-voltage use cases but demand updated resistor divider values and layout revision.

What is the thermal resistance (R_θJA) of TLV431IDBVT?

The junction-to-ambient thermal resistance (R_θJA) for TLV431IDBVT in its SC-70 (DCK) package is 206°C/W, as specified in Section 5.4 of the TI SLVS139Z datasheet. This value assumes standard JEDEC 2-layer board conditions (1 oz copper, 2S2P). Actual thermal performance depends on PCB copper area, airflow, and nearby heat sources-designers should verify junction temperature using T_J = T_A + (P_DISS × R_θJA) and keep below 125°C maximum rated junction temperature.