Texas Instruments TLVH431BCDCKT

Overview

TLVH431BCDCKT from Texas Instruments is a low-voltage adjustable precision shunt regulator in SC-70-6 package, delivering 1.24 V reference voltage with ±0.5% initial tolerance at 25°C, 0.25 Ω typical dynamic impedance, and operation down to 100 μA cathode current - enabling use in ultra-low-power isolated flyback feedback loops and on-board voltage monitoring.

For engineers reviewing the TLVH431BCDCKT datasheet, TLVH431BCDCKT pinout, TLVH431BCDCKT application, or TLVH431BCDCKT equivalent, key selection criteria include its 1.24 V minimum regulation voltage, –40°C to +125°C extended temperature grade (Q), SC-70 footprint compatibility, and verified performance as a Zener replacement in secondary-side SMPS regulation.

Technical Context

The TLVH431BCDCKT implements a precision bandgap reference and high-gain transconductance amplifier in a 3-terminal shunt topology. Its internal architecture forces the REF pin to 1.24 V when cathode current exceeds 100 μA and cathode-to-anode voltage ≥1.24 V, enabling closed-loop regulation via external resistor dividers or open-loop comparator operation with integrated reference.

Unlike the TL431, it operates from 1.24 V (not 2.5 V), supports cathode currents from 100 μA to 70 mA, and achieves 0.25 Ω dynamic impedance without requiring output capacitance for stability - validated across –40°C to +125°C for automotive and industrial applications.

Key Specifications

Pinout & Package

TLVH431BCDCKT uses the SC-70-6 (DCK) package (2.00 mm × 1.25 mm), featuring six terminals with two NC pins and substrate connection tied to ANODE.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431BIDCKR and TLVH432BCDBVR, TLVH431BCDCKT uniquely combines Q-grade temperature qualification, SC-70-6 footprint, and 6-pin terminal configuration - making it optimal for space-constrained, high-reliability applications where thermal headroom and long-term stability are critical.

Availability

TLVH431BCDCKT is available at Aetrix Electronics and suitable for isolated SMPS feedback, precision voltage monitoring, and low-power Zener replacement applications requiring stable component supply across automotive, industrial, and computing end equipment.

Supply support for TLVH431BCDCKT 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 over 50 years of innovation in precision analog ICs.

The TLVH431 family was designed specifically for low-voltage, low-power shunt regulation - addressing limitations of legacy TL431 in modern 1.8 V–3.3 V systems and enabling compact, efficient feedback in isolated power supplies.

FAQ

What is the maximum cathode voltage rating for TLVH431BCDCKT?

The absolute maximum cathode-to-anode voltage (V_KA) for TLVH431BCDCKT is 20 V. However, the recommended operating range is 1.24 V to 18 V. Exceeding 20 V risks permanent damage. This rating is confirmed in Section 5.1 Absolute Maximum Ratings of the TI SLVS555N datasheet, and applies identically across all TLVH431x variants including TLVH431BCDCKT.

Does TLVH431BCDCKT require an output capacitor for stability?

No, TLVH431BCDCKT is internally compensated and stable without an output capacitor between cathode and anode - a key advantage over many linear regulators. Stability with capacitive loads is addressed in Figures 5-15 through 5-17 of the datasheet, which provide phase-margin guidance for cases where external capacitance is added for filtering. TLVH431BCDCKT maintains stability across its full 100 μA–70 mA cathode current range in SC-70 packaging.

How does the substrate pin (Pin 6) on TLVH431BCDCKT affect PCB layout?

Pin 6 on TLVH431BCDCKT is the die substrate connection, internally tied to the ANODE. Per TI's Pin Functions table and Figure 4-2, it must be either soldered to the ANODE net or left unconnected - never tied to ground or floating independently. Incorrect handling can cause latch-up or ESD susceptibility. The SC-70-6 land pattern must assign this pad to the ANODE copper pour or omit solder mask opening entirely if unused.

Can TLVH431BCDCKT replace a standard Zener diode in existing designs?

Yes, TLVH431BCDCKT serves as a high-accuracy, low-leakage Zener replacement: it offers 0.5% V_REF tolerance (vs ±5% for 1N4728A), 0.02–0.1 μA off-state current (vs 0.5–5 μA), and sharp turn-on characteristics. To substitute, connect ANODE to ground, CATHODE to the rail being clamped, and REF to the divider network. No changes to resistor values are needed beyond verifying I_K ≥100 μA under worst-case conditions.

What is the thermal resistance (R_θJA) of TLVH431BCDCKT in its SC-70-6 package?

The junction-to-ambient thermal resistance (R_θJA) for TLVH431BCDCKT in the SC-70-6 (DCK) package is 259°C/W, as specified in Section 5.4 Thermal Information of the TI SLVS555N datasheet. This value assumes standard JEDEC 2S2P test board conditions. Actual board-level R_θJA will vary based on copper area, layer count, and airflow - design margins should account for ≥30°C additional rise above ambient at 70 mA cathode current.