Texas Instruments TLVH431AIDCKT

Overview

TLVH431AIDCKT from Texas Instruments is a low-voltage adjustable precision shunt regulator in SC-70 package, providing 1.24 V reference voltage with ±1% tolerance at 25°C, 0.25 Ω typical dynamic impedance, and operation from 1.24 V to 18 V output range across –40°C to +125°C. It serves as an error amplifier or voltage reference in isolated flyback SMPS feedback loops.

For engineers reviewing the TLVH431AIDCKT datasheet, TLVH431AIDCKT pinout, TLVH431AIDCKT application, or TLVH431AIDCKT equivalent, key selection criteria include cathode current range (100 μA–70 mA), reference voltage drift over temperature (±31 mV for Q-grade), ultra-low reference input current (0.1–0.5 μA), and SC-70 footprint compatibility for space-constrained power rail monitoring and data converter reference designs.

Technical Context

The TLVH431AIDCKT implements a bandgap-referenced op-amp driving a Darlington sink output stage, enabling sharp turn-on behavior and stable regulation without external compensation. Its internal 1.24 V reference is trimmed at wafer test to achieve ±1% initial accuracy (A-grade) and maintains thermal stability via on-chip curvature correction.

It operates in two functional modes: open-loop comparator mode (reference pin compared to internal threshold) and closed-loop shunt regulator mode (feedback from cathode to reference pin). In both, it requires ≥100 μA cathode current to enter linear regulation and sustain sufficient gain for accurate error amplification.

Key Specifications

Pinout & Package

TLVH431AIDCKT is packaged in a 6-pin SC-70 (DCK) with 2.00 mm × 1.25 mm body size. Pin 2 is substrate-connected and must be tied to ANODE or left open; pins 4 and 5 are NC (no internal connection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BIDCKT, TLVH431AIDCKT trades 0.5% reference accuracy for cost efficiency while retaining full thermal and dynamic performance; versus TLVH432AIDCKR, it requires different PCB layout due to non-interchangeable pin mapping despite identical functionality and package outline.

Availability

TLVH431AIDCKT is available at Aetrix Electronics and suitable for isolated flyback SMPS design, precision ADC reference circuits, low-leakage voltage monitoring, and Zener replacement applications requiring stable component supply across automotive, industrial, and medical electronics programs.

Supply support for TLVH431AIDCKT 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 TLVH431 family was designed for low-voltage, high-accuracy shunt regulation in space-constrained and thermally demanding applications including isolated DC/DC converters, data acquisition systems, and power rail supervision.

FAQ

What is the reference voltage tolerance of TLVH431AIDCKT at 25°C?

The TLVH431AIDCKT has a reference voltage tolerance of ±1% at 25°C, corresponding to a 1.24 V nominal value with a range of 1.228 V to 1.252 V. This A-grade specification is confirmed in Section 5.6 of the TI datasheet SLVS555N and applies specifically to the TLVH431A variant in SC-70 packaging. The TLVH431AIDCKT maintains this tolerance across its full operating temperature range when used within recommended conditions.

Can TLVH431AIDCKT replace a standard TL431 in existing designs?

TLVH431AIDCKT can replace TL431 only with circuit modifications: it requires ≥100 μA cathode current (vs 1 mA for TL431), operates down to 1.24 V (vs 2.5 V), and uses different pinout in SC-70. Direct substitution is not possible without adjusting feedback resistors, verifying minimum cathode current, and confirming layout compatibility. The TLVH431AIDCKT is not pin-compatible with TL431 in any package.

What is the minimum cathode current required for regulation in TLVH431AIDCKT?

The TLVH431AIDCKT requires a minimum cathode current of 100 μA to maintain regulation, as specified in Section 5.5 of the datasheet under IK(min). Below this threshold, open-loop gain drops significantly, causing loss of regulation accuracy and increased reference voltage deviation. This value is validated across –40°C to +125°C for the Q-grade version and applies directly to TLVH431AIDCKT in SC-70 packaging.

Does TLVH431AIDCKT require an output capacitor for stability?

No, TLVH431AIDCKT is internally compensated and stable without an output capacitor between cathode and anode. Section 7.3 of the datasheet explicitly states that external capacitance is optional. However, if added, capacitor selection must follow Figures 5-15 through 5-17 to avoid phase margin degradation-especially with capacitive loads exceeding 1 nF.

How does the SC-70 package of TLVH431AIDCKT compare in size to SOT-23-3?

The SC-70 package of TLVH431AIDCKT measures 2.00 mm × 1.25 mm, offering a 40% smaller footprint than the 2.92 mm × 1.30 mm SOT-23-3 (DBZ) variant per TI's package documentation. This reduction supports high-density PCB layouts in portable and modular power designs, while maintaining identical thermal resistance (RθJA = 259°C/W) and electrical performance as other SC-70 variants in the TLVH431 family.