STMicroelectronics LD29300P2M50R

Overview

LD29300P2M50R from STMicroelectronics is a 5.0 V fixed-output, 3 A low-dropout linear voltage regulator in P2PAK package with ±1% output tolerance at 25 °C, 0.4 V typical dropout at 3 A, and logic-controlled electronic shutdown. It delivers high-accuracy regulation for post-regulation of switching supplies and battery-powered systems requiring stable 5 V rail under high load.

For engineers reviewing the LD29300P2M50R datasheet, LD29300P2M50R pinout, LD29300P2M50R application, or LD29300P2M50R equivalent, key selection criteria include guaranteed 3 A output current, thermal/current protection, ground current as low as 45 mA at 3 A, and compatibility with 10 µF ceramic output capacitors.

Technical Context

This regulator uses a PMOS pass transistor architecture enabling ultra-low dropout (0.4 V typ. at 3 A) and near-zero reverse current during shutdown. Its internal reference achieves ±1% initial accuracy and maintains stability over –40 to +125 °C junction temperature range.

The device integrates thermal foldback, current limiting, and an inhibit input (VINH) that enables logic-level ON/OFF control with 0.8 V low threshold and 2 V high threshold. Output noise is specified at 200 µVRMS (10 Hz–100 kHz) at 100 mA load.

Key Specifications

Pinout & Package

P2PAK package: thermally enhanced surface-mount variant with exposed drain pad for direct PCB thermal conduction; compatible with standard TO-220 footprint but optimized for automated assembly and higher power density.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 5 V, 3 A LDO applications.

Compared with TSM10505TR and LP3878MRX-5.0, LD29300P2M50R uniquely balances 0.4 V dropout, ±1% accuracy, integrated shutdown, and 10 µF CO compatibility-making it optimal for space-constrained, battery-aware designs needing precise, controllable 5 V regulation.

Availability

LD29300P2M50R is available at Aetrix Electronics and suitable for computer systems, battery-powered instrumentation, and TV/monitor standby power requiring stable component supply across long production lifecycles.

Supply support for LD29300P2M50R 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, Switzerland, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The LD29300 series belongs to ST's high-current LDO portfolio, engineered specifically for post-regulation in power-constrained systems where ultra-low dropout, precision, and thermal robustness are mandatory.

FAQ

What is the minimum input voltage required to maintain 5.0 V output at 3 A load?

The minimum input voltage is 5.4 V, derived from the 5.0 V nominal output plus the typical 0.4 V dropout voltage at 3 A. The datasheet specifies absolute minimum VI as 6 V for LD29300#50 across temperature, ensuring margin for worst-case dropout (0.7 V max) and line regulation drift.

Can LD29300P2M50R be used without a heatsink?

Yes, for intermittent or low-duty-cycle 3 A loads with adequate PCB copper (≥4 cm² 2 oz copper on top/bottom layers). Continuous 3 A operation requires a heatsink or thermal pad connection to internal ground plane, as R_thJA is 60 °C/W in P2PAK - exceeding safe junction temperature without thermal enhancement.

Is an input capacitor required, and what value is recommended?

An input capacitor is mandatory for stability and transient suppression. ST recommends ≥330 nF ceramic (X7R or better) placed within 5 mm of the IN and GND pins. Larger values (e.g., 1–10 µF) improve high-frequency ripple rejection but are not required for basic functionality.

Does the VINH pin require a pull-up resistor when unused?

No. VINH is internally pulled up; leaving it unconnected defaults the device to ON mode. To ensure reliable startup in noisy environments, tie VINH to IN through a 100 kΩ resistor - this guarantees >2 V logic high while adding negligible current draw.