Texas Instruments TLV431BCLP

Overview

TLV431BCLP from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, 0.5% 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 cathode current, and supports secondary-side regulation in isolated flyback SMPSs.

For engineers reviewing the TLV431BCLP datasheet, TLV431BCLP pinout, TLV431BCLP application, or TLV431BCLP equivalent, key selection criteria include reference accuracy over temperature (±4 mV from 0°C to 70°C), ultra-small SC-70 package footprint, low minimum cathode current for regulation (55–100 µA), and stability without external compensation capacitors.

Technical Context

The TLV431BCLP implements an internally compensated shunt-regulator architecture with a precision bandgap reference and high-gain NPN-based error amplifier. Its open-loop comparator mode enables voltage monitoring with integrated reference, while closed-loop configuration-using two external resistors between cathode and reference pins-sets output voltage from 1.24 V to 6 V.

It operates down to 1.24 V cathode-anode voltage (VKA), requires no external capacitor for stability, and maintains 0.25 Ω dynamic impedance across 0.1 mA to 15 mA cathode current. The device's substrate-connected pin must be tied to anode or left floating per TI's pin function specification.

Key Specifications

Pinout & Package

TLV431BCLP uses the SC-70 (DCK) 6-pin package with 2.0 mm × 1.5 mm body size and 0.65 mm pitch. Pin 1 is CATHODE, Pin 3 is REF, Pin 6 is ANODE; Pins 4 and 5 are NC (no internal connection); Pin 2 is substrate-connected and must be tied to ANODE or left open.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431ACLPR, TLV431BCLP offers 0.5% reference accuracy critical for precision feedback loops; compared with TLVH431ILP, it trades voltage/current headroom for ultra-compact SC-70 packaging and lower quiescent current - making TLV431BCLP optimal for space- and power-constrained 3.3 V systems.

Availability

TLV431BCLP is available at Aetrix Electronics and suitable for isolated flyback SMPSs, precision voltage references, and low-power voltage monitoring applications requiring stable component supply and long-term manufacturability.

Supply support for TLV431BCLP 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The TLV431 family was designed specifically as a low-voltage, low-power replacement for TL431 in space-constrained and battery-operated systems requiring precise 1.24 V referencing and shunt regulation.

FAQ

What is the reference voltage tolerance of TLV431BCLP at 25°C?

The TLV431BCLP has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 1.24 V nominal reference with a range of 1.234 V to 1.246 V. This tight tolerance is specified in Section 5.7 of the TI datasheet SLVS139Z and applies exclusively to the TLV431B grade. TLV431BCLP maintains this accuracy without external trimming, supporting high-precision feedback in regulated power supplies.

Which package does TLV431BCLP use, and what are its dimensions?

TLV431BCLP uses the SC-70 (DCK) package, measuring 2.0 mm × 1.5 mm with 0.65 mm lead pitch. This ultra-small outline is confirmed in the "Package Information" table and Figure 4-5 of the TI datasheet. The SC-70 footprint is 40% smaller than SOT-23-3, enabling high-density placement in compact PCB designs such as wearables and sensor nodes where board space is constrained.

Can TLV431BCLP operate without an output capacitor?

Yes, TLV431BCLP is internally compensated and stable without an external output capacitor between cathode and anode - a key feature confirmed in Section 7.3 of the datasheet. This eliminates capacitor-related BOM cost, board area, and stability tuning effort. However, if a capacitor is added for noise filtering, Figure 5-19 provides phase-margin guidance to ensure stability across capacitive loads up to 1 nF.

What is the minimum cathode current required for regulation in TLV431BCLP?

The minimum cathode current (I_K(min)) for regulation in TLV431BCLP is 55 µA minimum and 100 µA maximum across the full temperature range (–40°C to 125°C), as specified in Section 5.7. At 25°C, typical I_K(min) is 80 µA. This ultra-low requirement enables TLV431BCLP to regulate in micropower applications such as energy harvesting interfaces and always-on supervision circuits where supply current is severely limited.

How does TLV431BCLP differ from TLV431ACLPR in practical design?

TLV431BCLP differs from TLV431ACLPR primarily in reference voltage tolerance: TLV431BCLP offers ±0.5% at 25°C versus ±1% for TLV431ACLPR. Both share identical SC-70 packaging, pinout, dynamic impedance (0.25 Ω), and temperature drift (±4 mV over 0°C–70°C). In practice, TLV431BCLP is selected for precision feedback loops demanding tighter regulation, while TLV431ACLPR suits cost-optimized designs where ±1% accuracy suffices - with no PCB or schematic changes required for substitution.