STMicroelectronics LD29080PTR

Overview

LD29080PTR from STMicroelectronics is an adjustable-output, 800 mA low-dropout linear voltage regulator in PPAK package, featuring 400 mV typical dropout at full load, ±1% output voltage accuracy over temperature, and logic-controlled electronic shutdown. It delivers stable bias for microcontroller cores, FPGA I/O banks, and analog sensor front-ends in space-constrained industrial and portable systems.

For engineers reviewing the LD29080PTR datasheet, LD29080PTR pinout, LD29080PTR application, or LD29080PTR equivalent, key selection criteria include dropout voltage at 800 mA, quiescent current vs. load, adjust pin current specification, thermal resistance (RthJA = 100 °C/W), and shutdown logic threshold compatibility with 3.3 V or 5 V control rails.

Technical Context

The LD29080PTR implements a high-accuracy bandgap reference (1.23 V typ.) with external resistor divider feedback on the ADJ pin, enabling programmable output from 1.23 V to (VI – 0.4 V). Its internal current and thermal limiting protect against overload and junction overheating without external components.

It features a dedicated INHIBIT terminal requiring ≥2 V to enable regulation - not internally pulled up - and draws only 130–180 µA in shutdown mode. Output noise is specified at 50 µVRMS (10 Hz–100 kHz) under 100 mA load, supporting noise-sensitive analog circuitry.

Key Specifications

Pinout & Package

PPAK (Power Package) thermally enhanced surface-mount package with exposed thermal pad (GND-connected), optimized for PCB heat dissipation in high-power density layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and ADM7172ACPZ-R7, the LD29080PTR uniquely balances 800 mA output, 0.4 V dropout, adjustable VO, and PPAK thermal performance - making it optimal for cost-sensitive, thermally constrained, programmable-rail applications where moderate noise is acceptable.

Availability

LD29080PTR is available at Aetrix Electronics and suitable for industrial automation controllers, portable medical instrumentation, automotive infotainment modules, and network edge hardware requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for LD29080PTR 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 LD29080PTR belongs to ST's high-accuracy, medium-current LDO family targeting post-regulation in power-constrained embedded systems where thermal efficiency, programmability, and robustness are prioritized over ultra-low noise.

FAQ

What is the minimum load current required for stable operation?

The LD29080PTR requires a minimum load current of 2 mA across its full operating temperature range (–40 to +125 °C) to prevent output voltage rise caused by output leakage current. This is specified in Note 4 of the Electrical Characteristics tables and applies to all output voltage configurations, including adjustable mode.

Can the INHIBIT pin be left floating?

No - the INHIBIT pin is not internally pulled up. If left floating, the device may enter undefined or disabled states. To guarantee ON mode, INHIBIT must be actively driven to ≥2 V (e.g., via MCU GPIO or resistor divider from VI); for OFF mode, tie directly to GND.

What output capacitor is required for stability?

A minimum 10 µF ceramic output capacitor (X5R/X7R, 6.3 V rating) is required for stability, as confirmed in Figure 4 and Section 5 (Typical Characteristics). The capacitor must be placed within 5 mm of the VO and GND pins; ESR should be <100 mΩ to maintain phase margin.

How does thermal performance differ between PPAK and DPAK packages?

Both PPAK and DPAK share identical R_thJC = 8 °C/W and R_thJA = 100 °C/W values per Table 4. However, PPAK's smaller footprint (6 × 6.2 mm vs. DPAK's 6.2 × 6.6 mm) and optimized thermal pad layout allow tighter placement in thermally dense layouts without sacrificing junction-to-ambient performance.