Texas Instruments TLV431AILPRE3

Overview

TLV431AILPRE3 from Texas Instruments is a low-voltage adjustable precision shunt regulator with 1.24 V reference voltage, ±1% initial tolerance at 25°C, 0.25 Ω typical dynamic impedance, and operation down to 1.24 V cathode-anode voltage - used as an integrated reference in isolated flyback secondary-side regulation, Zener replacement, and voltage monitoring circuits.

For engineers reviewing the TLV431AILPRE3 datasheet, TLV431AILPRE3 pinout, TLV431AILPRE3 application, or TLV431AILPRE3 equivalent, this page delivers verified electrical parameters, SC-70 package mapping, functional mode distinctions (open-loop comparator vs. closed-loop shunt regulator), thermal performance data, and real-world design implications for 3.3 V SMPS feedback and low-voltage sensing.

Technical Context

The TLV431AILPRE3 implements a bandgap-referenced error amplifier with Darlington output stage, enabling precise shunt regulation from 1.24 V to 6 V via two external resistors. Its internal reference is trimmed to 1.24 V ±1% at 25°C and exhibits 6 mV max drift over –40°C to +85°C industrial range.

It operates in two distinct functional modes: open-loop comparator mode (with integrated 1.24 V reference) requiring ≥55 µA cathode current for full gain, and closed-loop shunt regulator mode where feedback from cathode to reference pin establishes stable output voltage - both modes are internally compensated and stable without output capacitance.

Key Specifications

Pinout & Package

TLV431AILPRE3 is housed in a 6-pin SC-70 (DCK) package measuring 2.0 mm × 1.5 mm - 40% smaller footprint than SOT-23-3 - with exposed substrate pad connected to ANODE or left floating per TI specification.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV431ACLP and TLVH431ILP, TLV431AILPRE3 uniquely balances ultra-compact SC-70 packaging, industrial temperature rating, and ±1% reference accuracy - making it optimal for high-density 3.3 V power management where board space and thermal efficiency are constrained.

Availability

TLV431AILPRE3 is available at Aetrix Electronics and suitable for isolated flyback power supplies, voltage monitoring circuits, and low-voltage Zener replacement applications requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.

Supply support for TLV431AILPRE3 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, power management, and signal chain solutions.

The TLV431 family was designed specifically for low-voltage shunt regulation and integrated reference applications in space- and power-constrained systems - targeting 3.3 V/2.5 V/1.8 V switching-mode power supplies, battery management, and industrial sensing interfaces.

FAQ

What is the reference voltage tolerance of TLV431AILPRE3 at 25°C?

The TLV431AILPRE3 has a reference voltage tolerance of ±1% at 25°C, corresponding to a 1.24 V nominal V_REF with a range of 1.228 V to 1.252 V. This is confirmed in Section 5.6 of the TI SLVS139Z datasheet for TLV431A-grade devices. The 'A' suffix denotes the 1% grade, and TLV431AILPRE3 is fully specified to this tolerance across its operating conditions.

Which package does TLV431AILPRE3 use, and what are its dimensions?

TLV431AILPRE3 uses the SC-70 (DCK) package - a 6-pin surface-mount outline measuring 2.0 mm × 1.5 mm. Per TI's Package Information table, DCK is the only SC-70 variant offered for TLV431A, and TLV431AILPRE3 is explicitly ordered in this package. Its compact size provides a 40% smaller footprint than standard SOT-23-3 packages.

Can TLV431AILPRE3 operate as a comparator, and what is its minimum cathode current in that mode?

Yes, TLV431AILPRE3 operates as an open-loop comparator with integrated 1.24 V reference. In this mode, it requires a minimum cathode current of 55 µA to ensure full open-loop gain and fast response - specified in Section 5.6 as I_K(min) for TLV431A over the industrial temperature range. Below this, response slows significantly.

How does TLV431AILPRE3 differ from the standard TL431 in low-voltage applications?

TLV431AILPRE3 operates down to 1.24 V cathode-anode voltage and draws only 55–80 µA minimum cathode current, whereas TL431 requires ≥2.5 V V_KA and ≥1 mA I_K(min). This makes TLV431AILPRE3 viable in 1.8 V/2.5 V/3.3 V systems where TL431 cannot regulate - confirmed in Section 7.1 as "low power counterpart to TL431" with lower V_REF and I_K(min).

Is an output capacitor required for stability with TLV431AILPRE3?

No, TLV431AILPRE3 is internally compensated and stable without an output capacitor between cathode and anode - a key advantage over many linear regulators. TI confirms this in Section 7.3: "Unlike many linear regulators, TLV431 is internally compensated to be stable without an output capacitor." Capacitors may be added for noise filtering but are not required for loop stability.