STMicroelectronics L4931ABDT25TR

Overview

L4931ABDT25TR from STMicroelectronics is a very low dropout (LDO) linear voltage regulator in SO-8 package, delivering 2.5 V ±1% output at up to 250 mA with 0.4 V typical dropout at full load, 600 µA typical quiescent current in active mode, and logic-controlled shutdown. It serves as a local power rail regulator in automotive body control modules requiring AEC-Q100 qualification and extended temperature operation.

For engineers reviewing the L4931ABDT25TR datasheet, L4931ABDT25TR pinout, L4931ABDT25TR application, or L4931ABDT25TR equivalent, key selection criteria include its ±1% output accuracy at 25 °C, -40 to 125 °C automotive-grade operating range, TTL-compatible inhibit function, 2.2 µF minimum output capacitance requirement, and SO-8 thermal performance (R_thJA = 55 °C/W).

Technical Context

The L4931ABDT25TR integrates an internal PNP pass transistor, enabling ultra-low dropout operation down to 0.4 V at 250 mA while maintaining tight output regulation across line (±3 mV), load (±3 mV), and temperature (±25 mV over -25 to +85 °C). Its shutdown circuit accepts TTL-level logic input (V_IL ≤ 0.8 V, V_IH ≥ 2 V) to reduce quiescent current to 50 µA typ., supporting system-level power gating.

Designed for automotive environments, it features internal current limiting, thermal shutdown, and AEC-Q100 qualification per Grade 1 (-40 to 125 °C junction). The device achieves 75 dB supply voltage rejection at 120 Hz and 50 µV RMS output noise (10 Hz–100 kHz), making it suitable for noise-sensitive analog and microcontroller rails.

Key Specifications

Pinout & Package

Package: SO-8 (small outline, surface-mount, 150 mil width), with exposed pad for enhanced thermal dissipation (R_thJA = 55 °C/W, R_thJC = 20 °C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV73325PDBVR and NCP1117DT25T5G, the L4931ABDT25TR uniquely combines automotive qualification, 250 mA capability, sub-0.5 V dropout, and integrated shutdown in SO-8-enabling compact, reliable, and power-aware designs where functional safety and thermal constraints coexist.

Availability

L4931ABDT25TR is available at Aetrix Electronics and suitable for automotive body electronics, ADAS camera subsystems, and infotainment audio power rails requiring stable component supply, AEC-Q100 compliance, and long-term lifecycle support.

Supply support for L4931ABDT25TR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, specializing in automotive, industrial, and power management ICs with broad manufacturing and qualification capabilities.

The L4931 series belongs to ST's automotive-grade linear regulator product line, engineered specifically for robust, low-noise, and thermally efficient local power delivery in harsh-temperature vehicle subsystems.

FAQ

What is the maximum input voltage rating for L4931ABDT25TR?

The absolute maximum DC input voltage is 20 V, as specified in Table 2 of the datasheet. Operation above this level risks permanent damage. For sustained reliability in automotive applications, ST recommends limiting VIN to ≤18 V under transient conditions (e.g., load dump), with appropriate external clamping if needed.

Does L4931ABDT25TR require an input bypass capacitor?

Yes - a minimum 0.1 µF ceramic capacitor placed close to the VIN pin is required for high-frequency stability and transient response, as shown in Figure 3 (Test Circuits) and referenced in all electrical characteristic tables. Omitting it may cause oscillation or poor line transient recovery.

Can L4931ABDT25TR be used without the INH pin connected?

Yes - the INH pin is internally pulled up, so leaving it open defaults the device to active mode. However, for automotive systems requiring controlled shutdown, it must be driven to <0.8 V (e.g., via MCU GPIO) to achieve 50 µA quiescent current; floating INH yields ~600 µA IQ.

Is the SO-8 package of L4931ABDT25TR lead-free and RoHS compliant?

Yes - per ST's official packaging information (Order Code L4931ABDT25TR), the SO-8 variant uses lead-free matte tin plating and complies with EU RoHS Directive 2011/65/EU and REACH SVHC regulations, with full material declarations available upon request.