Texas Instruments TLVH431BIDCKT

Overview

TLVH431BIDCKT from Texas Instruments is a precision 3-terminal adjustable shunt voltage reference with 0.5% initial tolerance at 25°C, 1.24 V nominal reference voltage, and operation down to 1.24 V cathode-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 low-voltage Zener replacement in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH431BIDCKT datasheet, TLVH431BIDCKT pinout, TLVH431BIDCKT application, or TLVH431BIDCKT equivalent, key selection criteria include reference accuracy grade (B), SC-70 package footprint constraints, cathode current headroom for regulation, and compatibility with optocoupler-based secondary-side control in 3.3 V–5 V power rails.

Technical Context

The TLVH431BIDCKT implements 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 references, while closed-loop operation with resistive feedback from cathode to reference pin achieves adjustable output regulation from 1.24 V to 18 V.

It is internally compensated for stability without an output capacitor, though phase margin vs. capacitive load data (Figures 5-15–5-17) supports design of frequency-compensated feedback networks. The device operates with ≤0.5 μA reference terminal current and maintains <31 mV VREF deviation over its full –40°C to +125°C Q-grade temperature range.

Key Specifications

Pinout & Package

TLVH431BIDCKT uses the SC-70 (DCK) 6-pin package (2.00 mm × 1.25 mm), featuring three functional terminals and three no-connect (NC) or substrate pins. Pin 2 connects to the die substrate and must be tied to ANODE or left floating per layout guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BIDCKT, TLVH431BIDBVR offers superior thermal resistance but requires PCB redesign, while TLVH431BQDBZR provides identical form factor with enhanced temperature stability-making it a direct upgrade path for high-reliability deployments without layout changes.

Availability

TLVH431BIDCKT is available at Aetrix Electronics and suitable for isolated power supplies, precision analog sensing, and embedded voltage monitoring applications requiring stable component supply and guaranteed long-term sourcing.

Supply support for TLVH431BIDCKT 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, embedded processing, and connectivity solutions with emphasis on reliability, efficiency, and system-level integration.

The TLVH431 family was designed specifically for low-voltage, high-accuracy shunt regulation in isolated and non-isolated power conversion, voltage supervision, and precision reference applications across industrial, automotive, and communications end equipment.

FAQ

What is the reference voltage tolerance of TLVH431BIDCKT at 25°C?

The TLVH431BIDCKT has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal value with a range of 1.234 V to 1.246 V. This B-grade accuracy is confirmed in Section 5.7 of the datasheet and applies specifically to the TLVH431BIDCKT variant. The tolerance remains stable across its full operating temperature range of –40°C to +125°C, with total deviation limited to ±31 mV.

Which package type does TLVH431BIDCKT use, and what are its dimensions?

TLVH431BIDCKT uses the SC-70 (DCK) 6-pin package with nominal body dimensions of 2.00 mm × 1.25 mm. This ultra-small footprint is 40% smaller than the standard SOT-23-3, as documented in the "Device Information" table. Pin configuration includes CATHODE (Pin 1), ANODE (Pin 2), REF (Pin 3), and two NC pins (Pins 4 and 5), with Pin 2 also serving as the substrate connection.

Can TLVH431BIDCKT operate as a comparator, and how is it configured?

Yes, TLVH431BIDCKT can operate as a comparator in open-loop mode. It is configured by applying a voltage to the REF pin while supplying ≥100 μA cathode current-no feedback from CATHODE to REF is used. In this mode, the device compares the REF voltage to its internal 1.24 V reference and rapidly saturates the output, making it suitable for voltage monitoring and undervoltage lockout. Figure 8-2 and Section 7.4.1 confirm this functionality.

What is the minimum cathode current required for regulation in TLVH431BIDCKT?

The minimum cathode current required for regulation in TLVH431BIDCKT is 100 μA, as specified in Section 5.7 (IK(min)) under "TLVH43xB Electrical Characteristics." This value is guaranteed over the full –40°C to +125°C temperature range. Operation below this current may result in insufficient gain and unstable regulation, particularly at temperature extremes.

How does TLVH431BIDCKT handle capacitive loads on its cathode node?

TLVH431BIDCKT is internally compensated and stable without an output capacitor, but capacitive loads up to several hundred nanofarads can be supported with appropriate phase margin analysis. Figures 5-15 through 5-17 in the datasheet provide measured phase margin vs. capacitive load at multiple cathode voltages (1.25 V, 2.5 V, 5.0 V), enabling designers to select stable compensation networks for specific operating points without oscillation risk.