STMicroelectronics LD29300P2M18

Overview

LD29300P2M18 from STMicroelectronics is a 1.8 V, 3 A fixed-output low-dropout linear regulator in P2PAK package, featuring 0.4 V typical dropout at full load, ±1% output voltage tolerance at 25°C, and logic-controlled electronic shutdown. It delivers stable power for FPGA core rails, microprocessor I/O supplies, and battery-powered embedded systems requiring high accuracy and ultra-low dropout.

For engineers reviewing the LD29300P2M18 datasheet, LD29300P2M18 pinout, LD29300P2M18 application, or LD29300P2M18 equivalent, key selection criteria include guaranteed 3 A output current, thermal shutdown with internal current limiting, 62 dB supply voltage rejection at 120 Hz, and compatibility with low-ESR ceramic output capacitors down to 10 µF.

Technical Context

The LD29300P2M18 employs a PNP pass transistor architecture enabling sub-0.5 V dropout across its full 3 A load range while maintaining tight regulation. Its internal bandgap reference and error amplifier ensure ±1% output accuracy over temperature (−40°C to +125°C) and line/load variations.

It integrates logic-compatible enable control (V_IL = 0.8 V, V_IH = 2 V), thermal foldback protection, and short-circuit current limiting (4.5 A typical). The device operates with input voltages from 2.5 V to 30 V and supports stable operation with 10 µF ceramic output capacitance.

Key Specifications

Pinout & Package

P2PAK package: thermally enhanced surface-mount variant of TO-220 footprint, with exposed drain pad for PCB heat sinking. Thermal resistance: R_thj-case = 3°C/W, R_thj-amb = 60°C/W (on 2-layer 1-in² copper).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSM1083-1.8, LD29300P2M18 offers integrated enable control and lower quiescent current in active mode; versus TPS7A8300RGRT, it eliminates need for auxiliary bias rail but trades 50 µV_RMS higher output noise.

Availability

LD29300P2M18 is available at Aetrix Electronics and suitable for industrial PLCs, FPGA development platforms, and battery-powered edge sensors requiring stable component supply with long-term manufacturability.

Supply support for LD29300P2M18 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, power, microcontroller, 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 output, and robust thermal behavior are essential.

FAQ

What is the minimum input voltage required for LD29300P2M18 to regulate 1.8 V at 3 A?

The minimum operating input voltage is 2.5 V across the full temperature range (−40°C to +125°C). At 3 A load and 25°C, regulation is maintained with input as low as 2.2 V due to 0.4 V typical dropout - however, 2.5 V is the guaranteed specification limit per datasheet Absolute Maximum Ratings table.

Can LD29300P2M18 be used without an input bypass capacitor?

No - an input capacitor (CI = 330 nF ceramic minimum) is required for stability and transient response, as specified in all electrical characterization test conditions. Omitting CI risks oscillation and degraded PSRR, especially under dynamic load changes common in microprocessor applications.

Does the LD29300P2M18 require a specific output capacitor ESR range?

No - unlike older LDOs, LD29300P2M18 is optimized for low-ESR ceramic capacitors (10 µF minimum, X5R/X7R dielectric). The datasheet confirms stable operation with ESR as low as 5 mΩ; tantalum or aluminum electrolytics are not recommended due to higher ESR and aging effects.

How does thermal performance differ between P2PAK and D2PAK packages for this part?

P2PAK has identical R_thj-case (3°C/W) to D2PAK but higher R_thj-amb (60°C/W vs. 50°C/W), meaning it relies more heavily on PCB copper area for heat dissipation. For 3 A continuous operation at ambient >60°C, P2PAK requires ≥2 in² of 2-oz copper connected to the exposed pad to maintain junction temperature below 125°C.