STMicroelectronics LD39020DTPU25R

Overview

LD39020DTPU25R from STMicroelectronics is a 2.5 V, ±2% tolerance, 200 mA ultra-low-dropout linear regulator in DFN4 1x1 package, featuring 200 mV typical dropout at 200 mA, 20 µA typical quiescent current at no load, and logic-controlled enable with <0.1 µA shutdown current - deployed in mobile phone baseband power rails and portable media player core supplies.

For engineers reviewing the LD39020DTPU25R datasheet, LD39020DTPU25R pinout, LD39020DTPU25R application, or LD39020DTPU25R equivalent, key selection criteria include dropout voltage under 200 mA load, output accuracy over –40 °C to 125 °C, PSRR >80 dB at 1 kHz, ceramic capacitor compatibility (≥0.47 µF), and thermal/overcurrent protection behavior in space-constrained battery-powered designs.

Technical Context

The LD39020DTPU25R integrates a bandgap reference, error amplifier, and PMOS pass transistor in a fixed-output LDO architecture. Its internal soft-start limits inrush current during enable transition, and the optional output discharge MOSFET (enabled in DT variants) actively pulls VOUT to GND when EN is low.

Stabilized with ≥0.47 µF ceramic output capacitance, it achieves 80 dB PSRR at 1 kHz and 45 µV_RMS integrated noise (10 Hz–100 kHz). Thermal shutdown triggers at 160 °C with 20 °C hysteresis, and internal current limiting caps short-circuit current at 250–350 mA.

Key Specifications

Pinout & Package

LD39020DTPU25R uses the DFN4 1x1 package: 4-pin, 1 mm × 1 mm body, 0.4 mm max height, exposed thermal pad connected to GND for enhanced thermal dissipation (R_thJA = 250 °C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B252MR-G and RT9013-25GB, LD39020DTPU25R offers superior PSRR (80 dB), integrated soft-start and discharge, and smallest footprint - making it optimal for ultra-compact, noise-sensitive, and fast-sequencing battery-powered systems.

Availability

LD39020DTPU25R is available at Aetrix Electronics and suitable for mobile phones, digital still cameras, and portable media players requiring stable component supply with tight voltage accuracy, low quiescent current, and high thermal reliability.

Supply support for LD39020DTPU25R 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, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

LD39020 belongs to ST's high-accuracy, ultra-low-I_Q LDO family targeting space- and power-constrained portable electronics - engineered specifically for battery longevity, thermal resilience, and seamless integration with ceramic capacitors.

FAQ

What is the minimum input voltage required for LD39020DTPU25R to maintain regulation at full 200 mA load?

The LD39020DTPU25R requires VIN ≥ 2.7 V to sustain 2.5 V output at 200 mA, based on its 200 mV typical dropout voltage. At worst-case 350 mV dropout (–40 °C to 125 °C), VIN must be ≥ 2.85 V. Operation below 1.5 V input is prohibited per absolute maximum ratings.

Does LD39020DTPU25R require an external capacitor on the EN pin for noise immunity?

No external capacitor is required on the EN pin. The device features internal hysteresis and filtering; EN logic thresholds are specified as 0.4 V (max low) and 1 V (min high) across –40 °C to 125 °C. Layout best practice is to route EN away from noisy traces and keep trace length short.

Can LD39020DTPU25R be used with a 0.22 µF output capacitor?

No - 0.22 µF is below the 0.47 µF minimum recommended for stability across temperature and load. Figure 17 in DS9956 confirms instability risk below 0.47 µF, especially with ESR < 1 Ω. Using 0.22 µF may cause oscillation or poor transient response; 0.47 µF X5R/X7R is the validated minimum.

Is the thermal pad of the DFN4 1x1 package electrically connected internally?

Yes - the exposed thermal pad is internally connected to GND. It must be soldered to a PCB copper pour tied to the system ground plane to achieve rated R_thJA = 250 °C/W and ensure reliable thermal performance under 200 mA continuous load.