Texas Instruments TLVH431BCDBVT

Overview

TLVH431BCDBVT from Texas Instruments is a precision 3-terminal adjustable shunt voltage reference IC operating down to 1.24 V with ±0.5% initial tolerance at 25°C, 100 μA–70 mA cathode current range, and 0.25 Ω typical dynamic impedance - used for secondary-side regulation in isolated 3.3 V flyback SMPSs.

For engineers reviewing the TLVH431BCDBVT datasheet, TLVH431BCDBVT pinout, TLVH431BCDBVT application, or TLVH431BCDBVT equivalent, key selection considerations include its B-grade reference accuracy, SC-70-6 package footprint, -40°C to +125°C operation (Q-grade), ultra-low I_ref (0.1–0.5 μA), and compatibility with optocoupler-based feedback loops requiring sharp turn-on and stable regulation below 2.5 V.

Technical Context

The TLVH431BCDBVT implements an internal 1.24 V bandgap reference and high-gain transconductance amplifier driving a Darlington output stage. Its closed-loop operation enables precise voltage regulation via external resistor dividers, while open-loop use supports comparator functions with integrated reference.

It features active output circuitry delivering sharp turn-on characteristics and inherent stability without mandatory output capacitance - though phase margin vs. capacitive load is characterized up to 100 nF. Thermal drift is specified across industrial and automotive temperature ranges, with V_REF deviation ≤31 mV over –40°C to +125°C for Q-grade variants.

Key Specifications

Pinout & Package

TLVH431BCDBVT is packaged in a 6-pin SC-70 (DCK) package measuring 2.00 mm × 1.25 mm - offering a 40% smaller footprint than SOT-23-3. The package includes exposed substrate connection (Pin 2) requiring tie to ANODE or floating per datasheet guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BIDBVT, TLVH431BCDBVT provides guaranteed operation up to +125°C - critical for under-hood or high-ambient industrial use - while TLVH431BQDBVT adds formal automotive qualification without altering baseline functionality.

Availability

TLVH431BCDBVT is available at Aetrix Electronics and suitable for isolated flyback SMPSs, precision data converter references, low-leakage Zener replacements, and rail-monitoring circuits requiring stable component supply across automotive, industrial, and telecom end equipment.

Supply support for TLVH431BCDBVT 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 specializing in analog, embedded processing, and power management technologies, with decades of leadership in precision reference and power IC design.

The TLVH431 family was engineered to extend shunt reference capability into sub-2.5 V systems - addressing demand for accurate, low-power, small-footprint voltage references in space-constrained and thermally demanding applications.

FAQ

What is the reference voltage tolerance of TLVH431BCDBVT at 25°C?

The TLVH431BCDBVT has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a V_REF range of 1.234 V to 1.246 V. This B-grade accuracy is confirmed in Section 5.7 of the TI SLVS555N datasheet and applies specifically to the 'B' suffix variant. TLVH431BCDBVT maintains this tolerance across its full operating temperature range when used within recommended conditions.

Which package does TLVH431BCDBVT use, and how many pins are functional?

TLVH431BCDBVT uses the SC-70-6 (DCK) package - a 2.00 mm × 1.25 mm surface-mount outline with six physical terminals. Only three pins are electrically functional: CATHODE (Pin 1), REF (Pin 5), and ANODE (Pin 3). Pins 2, 4, and 6 are NC (no internal connection), with Pin 2 designated as substrate tie requiring connection to ANODE or floating per TI layout guidance.

Can TLVH431BCDBVT replace TL431 in existing designs?

TLVH431BCDBVT can replace TL431 only in designs where the lower 1.24 V reference and reduced minimum cathode current (100 μA vs. 1 mA) are compatible. It is not pin-compatible - TL431 uses TO-92/SOT-23-3 while TLVH431BCDBVT uses SC-70-6. Direct substitution requires PCB redesign, updated resistor values, and validation of loop stability due to differing gain and impedance profiles.

What is the minimum cathode current required for regulation in TLVH431BCDBVT?

The minimum cathode current required for regulation in TLVH431BCDBVT is 100 μA at 25°C, with a maximum of 120 μA over the full –40°C to +125°C temperature range. This value is specified in Section 5.5 (TLVH43x Electrical Characteristics) and is critical for ensuring proper amplifier biasing and regulation accuracy - falling below this current risks loss of regulation and increased output impedance.

Does TLVH431BCDBVT require an output capacitor for stability?

No, TLVH431BCDBVT is internally compensated and stable without an output capacitor between CATHODE and ANODE. However, if a capacitor is added for noise filtering or transient response shaping, TI provides phase margin vs. capacitive load curves (Figures 5-15 to 5-17) showing stable operation up to 100 nF depending on cathode voltage - enabling informed capacitor selection without risking oscillation.