STMicroelectronics LD29080DT15R

Overview

LD29080DT15R from STMicroelectronics is a fixed-output 1.5 V, 800 mA low-dropout linear regulator in DPAK package, featuring 0.4 V typical dropout at full load, ±1% output voltage 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 LD29080DT15R datasheet, LD29080DT15R pinout, LD29080DT15R application, or LD29080DT15R equivalent, key selection factors include guaranteed 800 mA output current, 0.4 V dropout at 800 mA, 1.5 V ±1% tolerance across –40 °C to +125 °C, thermal/current protection, and inhibit-controlled shutdown functionality.

Technical Context

The LD29080DT15R integrates internal current limiting and thermal shutdown circuitry, with an inhibit input (INH) requiring ≥2 V to maintain ON state-internally not pulled up. Its reference voltage is trimmed to 1.23 V, enabling precise 1.5 V output via internal resistor divider.

Designed for medium-current loads, it operates with input voltages from 2.5 V to 13 V and maintains regulation down to 0.4 V VIN–VOUT differential at 800 mA. Output noise is 60 µVRMS (10 Hz–100 kHz), and supply voltage rejection reaches 75 dB at 120 Hz.

Key Specifications

Pinout & Package

DPAK (TO-252) package: thermally enhanced surface-mount outline with exposed drain pad for PCB heat sinking; footprint matches JEDEC MS-012AC standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout regulator applications.

Compared with LD29080PT15R, the DPAK variant offers identical regulation performance with simpler 3-pin routing and established thermal design; versus LDL1117S15R, LD29080DT15R provides decisive advantages in dropout, accuracy, and controllability-justifying its use in precision, low-voltage, or battery-constrained designs.

Availability

LD29080DT15R is available at Aetrix Electronics and suitable for industrial PLC I/O modules, portable instrumentation, set-top box AV processing, and power supply post-regulation requiring stable component supply with long-term manufacturability.

Supply support for LD29080DT15R 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, specializing in power management, analog, microcontrollers, and automotive ICs.

The LD29080 series belongs to ST's high-accuracy, medium-current LDO portfolio, engineered for applications demanding ultra-low dropout, tight regulation, and robust protection in harsh thermal environments.

FAQ

What is the minimum input voltage required for regulation at 1.5 V output?

The LD29080DT15R requires a minimum input voltage of 2.5 V to maintain regulation, as specified in Table 5. At 800 mA load, the 0.4 V typical dropout means 1.9 V input is sufficient-but 2.5 V is the absolute minimum per datasheet to guarantee operation across temperature and process variation.

Does the inhibit pin require a pull-up resistor?

No. The inhibit pin (Pin 1) is not internally pulled up; to ensure reliable ON-state operation, it must be actively driven to ≥2 V (e.g., tied to VI or controlled by GPIO). Leaving it floating may cause unpredictable shutdown due to noise or leakage.

Can LD29080DT15R be used without an output capacitor?

No. The datasheet mandates a minimum 10 µF ceramic output capacitor (CO) for stability, as confirmed in all electrical test conditions. Omitting it risks oscillation, poor transient response, and potential damage under load steps.

How does thermal performance differ between DPAK and SOT-223 packages?

DPAK (LD29080DT15R) has R_thJA = 100 °C/W and R_thJC = 8 °C/W; SOT-223 (e.g., LD29080S15R) has R_thJA = 110 °C/W and R_thJC = 25 °C/W. DPAK's lower junction-to-case resistance enables more effective heat transfer to PCB copper, making it preferable for sustained 800 mA operation.