STMicroelectronics LD39020DTPU47R

Overview

LD39020DTPU47R from STMicroelectronics is a 4.7 V, ±0.5 % accuracy, 200 mA ultra-low-dropout linear regulator in DFN4 1x1 package, featuring 200 mV typical dropout at full load, 20 µA quiescent current at no load, and logic-controlled shutdown. It delivers stable power to core rails in space-constrained, battery-powered systems such as digital still cameras and portable media players.

For engineers reviewing the LD39020DTPU47R datasheet, LD39020DTPU47R pinout, LD39020DTPU47R application, or LD39020DTPU47R equivalent, key selection criteria include output voltage tolerance, dropout behavior under 200 mA load, thermal performance in DFN4 1x1, soft-start timing, and compatibility with 0.47 µF ceramic output capacitors.

Technical Context

The LD39020DTPU47R employs a bandgap-referenced error amplifier and internal PMOS pass transistor to regulate output voltage with high line/load regulation (±10 mV load regulation, 0.02 %/V line regulation) across –40 °C to 125 °C. Its integrated soft-start limits inrush current without external components, achieving 100 µs turn-on time.

It includes logic-enabled shutdown (EN pin), internal thermal shutdown at 160 °C with 20 °C hysteresis, and overcurrent protection. The optional output discharge MOSFET (present in "D" variants like LD39020DTPU47R) actively discharges VOUT when EN is low, supporting fast system power-down sequencing.

Key Specifications

Pinout & Package

LD39020DTPU47R is housed in a thermally enhanced DFN4 1x1 mm, 4-pin package with exposed thermal pad (connected to GND). This ultra-compact footprint supports high-density PCB layouts while enabling efficient heat dissipation via PCB copper pour.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, low-IQ LDO applications.

Compared with XC6210B472MR-G and RT9080AL-47GJ5, LD39020DTPU47R uniquely combines ±0.5 % accuracy, integrated soft-start, and output discharge in a 1x1 mm DFN-making it optimal for miniaturized, fast-sequencing, high-precision portable power rails.

Availability

LD39020DTPU47R is available at Aetrix Electronics and suitable for digital still cameras, portable media players, tablet auxiliary rails, and wireless headset SoC power management requiring stable component supply, long-lifecycle support, and consistent parametric performance.

Supply support for LD39020DTPU47R 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-IQ LDO family targeting battery-powered portable electronics where minimal standby consumption, small footprint, and precise voltage regulation are mandatory design requirements.

FAQ

What is the minimum input voltage required for LD39020DTPU47R to maintain regulation at 200 mA?

The LD39020DTPU47R requires VIN ≥ VOUT + VDROP. With a typical dropout of 200 mV at 200 mA, the minimum functional input is 4.9 V. Absolute maximum ratings allow VIN as low as 1.5 V, but regulation fails below 4.9 V under full load. Derating is recommended above 85 °C due to increased dropout.

Can LD39020DTPU47R operate with a 0.22 µF output capacitor?

No. While the device remains stable down to 220 nF under ideal conditions, ST specifies a minimum of 0.47 µF ceramic capacitor (X5R/X7R) for guaranteed stability across temperature, input voltage, and load variations per Figure 17. Using 0.22 µF risks oscillation or poor transient response, especially at high ambient temperatures.

Does LD39020DTPU47R require an input capacitor, and what value is recommended?

Yes - a minimum 1 µF ceramic input capacitor is required and must be placed adjacent to the IN pin and returned to a clean analog ground. This capacitor filters high-frequency noise and supplies peak current during load transients. X5R or X7R dielectrics are recommended for stable ESR over temperature.

How does the output discharge function behave during shutdown?

When EN is pulled low, the internal 100 Ω NMOS switch activates between VOUT and GND, discharging the output capacitor rapidly. Typical discharge time to <100 mV is <1 ms with a 10 µF load capacitor. This prevents floating voltages that could cause latch-up or unintended wake-up in downstream ICs.