STMicroelectronics LD29150DT80R

Overview

LD29150DT80R from STMicroelectronics is a 1.5 A, fixed-output (8.0 V) low-dropout linear voltage regulator in PPAK package, featuring 400 mV typical dropout at full load, ±1% output accuracy over temperature, and logic-controlled electronic shutdown. It delivers stable power for post-regulation in switching supplies and battery-powered systems where ultra-low dropout and ground current are critical.

For engineers reviewing the LD29150DT80R datasheet, LD29150DT80R pinout, LD29150DT80R application, or LD29150DT80R equivalent, key selection criteria include guaranteed 1.5 A output current, thermal shutdown at 150 °C, 200 µVRMS output noise (at 5 V version), adjustable/enable functionality via INH pin, and compatibility with 10 µF ceramic output capacitors.

Technical Context

The LD29150DT80R implements a high-accuracy bandgap reference with internal error amplifier and PMOS pass transistor, enabling stable regulation with minimal headroom. Its fixed 8.0 V output is trimmed during production to ±1% at 25 °C and maintains ≤1.0% load regulation across 10 mA–1.5 A.

It integrates thermal shutdown (150 °C), short-circuit current limiting (2.2 A), and logic-compatible inhibit input (VIH = 2 V, VIL = 0.8 V) for system-level power sequencing. Dropout voltage remains ≤0.7 V up to 1.5 A and −40 to +125 °C junction temperature.

Key Specifications

Pinout & Package

LD29150DT80R uses the PPAK (Power Package) thermally enhanced surface-mount package with exposed thermal pad. This package provides R_thJC = 8 °C/W for efficient heat transfer to PCB copper.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and NCP1117DT80T5G, the LD29150DT80R uniquely combines 1.5 A output, 0.4 V dropout, integrated enable, and ±1% accuracy in a thermally optimized PPAK-making it the only viable choice for high-current, space-constrained, and sequenced 8 V rail designs.

Availability

LD29150DT80R is available at Aetrix Electronics and suitable for monitor power supplies, computer system rails, battery-powered instruments, and VCR/TV series regulators requiring stable component supply, long-term lifecycle support, and consistent parametric performance.

Supply support for LD29150DT80R 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 silicon solutions for automotive, industrial, and consumer markets since 1987.

The LD29150 series belongs to ST's high-current LDO portfolio, engineered specifically for post-regulation in power-constrained systems where minimal dropout, high accuracy, and robust protection are mandatory-targeting industrial automation, broadcast equipment, and portable instrumentation.

FAQ

What is the minimum input voltage required for LD29150DT80R to regulate 8.0 V at 1.5 A?

The minimum input voltage is 8.4 V, derived from the 0.4 V typical dropout voltage added to the 8.0 V nominal output. At 1.5 A and −40 to +125 °C, dropout remains ≤0.7 V per datasheet Table 7, so 8.7 V ensures regulation across temperature and process variation. Input below 8.4 V causes output to droop proportionally.

Can LD29150DT80R be used with ceramic output capacitors?

Yes-ST specifies stability with ≥10 µF ceramic output capacitors (X5R/X7R), confirmed in Figure 18 of the datasheet. The device's internal compensation eliminates need for ESR-based damping, enabling low-ESR ceramics that reduce board area and improve transient response versus tantalum or aluminum electrolytics.

Does LD29150DT80R require an input bypass capacitor?

Yes-a 330 nF ceramic capacitor is recommended between IN and GND, placed close to the device pins. This is specified in all electrical characteristic test conditions (e.g., Table 4–8) and suppresses high-frequency noise from upstream sources, preventing instability or erratic enable behavior due to supply bounce.

How does the INH pin behave during power-up?

The INH pin defaults to functional high-impedance state; regulator remains OFF until INH is actively driven ≥2 V. No pull-up/pull-down is internal. To ensure predictable startup, tie INH to a controlled GPIO or use an RC delay network-otherwise, floating INH may cause erratic turn-on or oscillation during input ramp-up.