STMicroelectronics LF25ABV

Overview

LF25ABV from STMicroelectronics is a 2.5 V fixed-output, very low dropout (LDO) linear regulator in PENTAWATT-5 package with logic-controlled shutdown, delivering up to 500 mA output current, 0.35 V typical dropout at 500 mA, ±1% output voltage accuracy at 25°C, and 50 µA quiescent current in OFF mode. It serves as a local power supply for microcontroller cores, sensor interfaces, and RF front-ends in battery-powered industrial and automotive control modules.

For engineers reviewing the LF25ABV datasheet, LF25ABV pinout, LF25ABV application, or LF25ABV equivalent, key selection criteria include dropout voltage at full load, shutdown logic compatibility (TTL), thermal resistance (R_thJC = 3°C/W), stability with 2.2 µF ceramic output capacitor, and operation across –40°C to 125°C junction temperature.

Technical Context

The LF25ABV implements a PNP pass transistor architecture enabling ultra-low dropout performance, with internal current and thermal limiting for robustness. Its 5-pin PENTAWATT configuration includes dedicated IN, OUT, GND, SHUTDOWN (pin 2, TTL-compatible), and ADJ/SENSE (pin 5) terminals-enabling precise remote sensing or external adjustment when used with feedback resistors.

It achieves 82 dB supply voltage rejection at 120 Hz and maintains 50 µV RMS output noise (10 Hz–100 kHz), supporting noise-sensitive analog and mixed-signal circuits. The device operates from 3.5 V to 16 V input and sustains regulation down to 2.85 V input at 500 mA load due to its 0.4 V min dropout.

Key Specifications

Pinout & Package

PENTAWATT-5 (vertical mount, 5-terminal) package with integrated heat slug; TO-220FP footprint compatible, R_thJC = 3°C/W, R_thJA = 50°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LDL112PU25R and TPS7A0525PDQNR, LF25ABV uniquely combines 500 mA drive capability, integrated TTL shutdown, AEC-Q100 readiness (per LF00 series qualification), and PENTAWATT thermal performance-making it the only option among the three suitable for high-current, thermally demanding, and automotive-grade 2.5 V local regulation.

Availability

LF25ABV is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, portable medical sensor hubs, and smart energy meter MCU cores requiring stable component supply, long-term lifecycle support, and AEC-Q100-aligned reliability.

Supply support for LF25ABV 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, designing and manufacturing microcontrollers, power management ICs, sensors, and automotive-grade components.

The LF00 series was developed specifically for low-noise, low-power, high-reliability local regulation in automotive and industrial environments-emphasizing ultra-low dropout, shutdown control, and extended temperature operation.

FAQ

What is the minimum input voltage required for regulation at 500 mA output?

The LF25ABV maintains regulation down to an input voltage of 2.85 V at 500 mA load, calculated as V_OUT + V_DROP(max) = 2.5 V + 0.35 V. This enables use with discharged LiFePO₄ cells (nominal 3.2 V, end-of-discharge ~2.8 V) without dropout-induced reset events.

Can the ADJ/SENSE pin be left floating in fixed-output configuration?

No. In fixed 2.5 V operation, pin 5 (ADJ/SENSE) must be directly connected to the OUT pin. Leaving it floating causes undefined regulation behavior and potential output instability. The internal feedback network is only valid when pin 5 is shorted to OUT.

Is LF25ABV qualified for automotive applications?

Yes. As part of the LF00 series, LF25ABV is manufactured and tested per AEC-Q100 Grade 1 (–40°C to +125°C) requirements. Its thermal performance (R_thJC = 3°C/W), shutdown functionality, and wide input range make it suitable for body electronics, instrument clusters, and ADAS domain controllers.

Does LF25ABV require an input capacitor?

Yes. A 0.1 µF ceramic capacitor is required between IN and GND, placed within 5 mm of the device pins. This stabilizes the internal reference and prevents oscillation during transient load steps; omission risks output overshoot and sustained ringing under dynamic loads.