STMicroelectronics LD29150P2T33R

Overview

LD29150P2T33R from STMicroelectronics is a fixed-output 3.3 V, 1.5 A low-dropout linear regulator in PPAK package with 400 mV typical dropout at full load, ±1% output voltage accuracy over temperature, and logic-controlled electronic shutdown. It delivers stable post-regulation for switching power supplies and powers sensitive analog/digital circuitry in battery-powered systems where ultra-low dropout and ground current are critical.

For engineers reviewing the LD29150P2T33R datasheet, LD29150P2T33R pinout, LD29150P2T33R application, or LD29150P2T33R equivalent, key selection criteria include guaranteed 1.5 A output current, thermal shutdown at 150 °C, 132 µV_RMS output noise (10 Hz–100 kHz), and compatibility with 10 µF ceramic output capacitors.

Technical Context

The LD29150P2T33R employs a high-accuracy bandgap reference and internal current-limiting circuitry to maintain ±1% output regulation across –40 °C to +125 °C junction temperature and 10 mA–1.5 A load range. Its PPAK thermally enhanced package achieves 8 °C/W junction-to-case thermal resistance, enabling sustained 1.5 A operation without external heatsinking under typical PCB copper area conditions.

It integrates logic-compatible inhibit control (V_IL = 0.8 V, V_IH = 2 V) for system-level power sequencing and features internal short-circuit protection (2.2 A limit) and thermal shutdown (150 °C). Dropout voltage remains ≤0.4 V up to 1.5 A, supporting operation with input as low as 3.7 V while maintaining regulated 3.3 V output.

Key Specifications

Pinout & Package

LD29150P2T33R uses ST's PPAK (Power Package) thermally optimized surface-mount package with exposed thermal pad for enhanced heat dissipation. The package measures 6.0 × 6.6 mm with 1.0 mm height and supports reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSM10833D and MCP1826T-3302E/DB, LD29150P2T33R offers superior thermal performance (R_thJC = 8 °C/W), integrated shutdown control, and lower output noise-critical for high-reliability, high-current, and noise-sensitive embedded systems.

Availability

LD29150P2T33R is available at Aetrix Electronics and suitable for industrial PLC I/O modules, portable medical devices, set-top box power management, and automotive infotainment core supply requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LD29150P2T33R 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 microcontrollers, power management ICs, sensors, and analog components for industrial, automotive, and consumer markets.

The LD29150 series belongs to ST's high-current LDO portfolio, engineered specifically for post-regulation in power-constrained and thermally demanding applications where ultra-low dropout, precision output, and robust protection are mandatory.

FAQ

What is the minimum input voltage required for LD29150P2T33R to maintain regulation at 1.5 A?

The minimum input voltage is calculated as V_OUT + V_DROP = 3.3 V + 0.4 V = 3.7 V. At 1.5 A and –40 °C to +125 °C, the device maintains regulation down to 3.7 V input; below this, output voltage drops proportionally. Input must not exceed 13 V to avoid automatic shutdown.

Can LD29150P2T33R operate without an output capacitor?

No. A minimum 10 µF low-ESR ceramic capacitor is required at the OUT pin for stability, as confirmed in Figure 18 of the datasheet. Omitting it causes oscillation and potential damage. The capacitor must be placed within 5 mm of the OUT and GND pins with short, wide traces.

How does the INH pin behave during power-up sequences?

The INH pin defaults to enabled (regulator ON) when left unconnected or pulled high via ≥100 kΩ resistor. To ensure controlled startup, tie INH to a microcontroller GPIO that asserts high only after input voltage stabilizes above 3.7 V and system reset completes.

Is the EPAD on LD29150P2T33R electrically connected internally?

Yes-the exposed thermal pad (EPAD) is internally connected to GND. It must be soldered to a dedicated PCB GND plane with ≥4 thermal vias (0.3 mm diameter) to achieve the specified 8 °C/W junction-to-case thermal resistance and sustain 1.5 A continuous output.