STMicroelectronics LD59030DTPU25R

Overview

LD59030DTPU25R from STMicroelectronics is a 300 mA ultra-low-dropout linear voltage regulator with fixed 2.5 V output, 135 mV typical dropout at 300 mA, ±1 % output voltage accuracy at 25 °C, and logic-controlled enable input. It operates from 1.5 V to 5.5 V input and delivers stable power to low-power microcontrollers and RF transceivers in space-constrained portable devices.

For engineers reviewing the LD59030DTPU25R datasheet, LD59030DTPU25R pinout, LD59030DTPU25R application, or LD59030DTPU25R equivalent, key selection criteria include dropout performance at 300 mA load, 28 µA quiescent current at no load, thermal shutdown behavior, soft-start timing (145 µs), and compatibility with 0.47 µF ceramic output capacitors in DFN4 1×1 packaging.

Technical Context

The LD59030DTPU25R integrates a bandgap reference, error amplifier, and internal PMOS pass transistor in a feedback loop that maintains regulation across -40 °C to 125 °C junction temperature. Its current fold-back protection activates when output voltage drops below 90 % of nominal, limiting short-circuit current to 120–170 mA.

Enable control is implemented via a CMOS-compatible input (VEN low = shutdown, <0.4 V; high = active, >1 V), driving an internal gate driver that controls both the main pass element and optional discharge MOSFET. The thermal pad is electrically tied to GND and rated for 1000 V HBM ESD tolerance.

Key Specifications

Pinout & Package

LD59030DTPU25R uses the DFN4 1×1 mm package with exposed thermal pad connected to GND. Pin 1 (OUT) carries regulated output; Pin 2 (GND) serves as common return and thermal path; Pin 3 (EN) accepts logic-level enable signal; Pin 4 (IN) supplies input voltage. Thermal pad must be soldered to PCB ground plane for thermal dissipation and ESD robustness.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B252MR-G and ADP160ACBZ-2.5-R7, LD59030DTPU25R uniquely combines 300 mA drive, 135 mV dropout, integrated enable + discharge, and DFN4 1×1 footprint - making it optimal for compact, battery-sensitive systems requiring full power sequencing control.

Availability

LD59030DTPU25R is available at Aetrix Electronics and suitable for wearable electronics, industrial IoT sensors, automotive cabin modules, and portable medical devices requiring stable component supply with long-term lifecycle assurance.

Supply support for LD59030DTPU25R 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, microcontroller, power, and sensing solutions for industrial, automotive, and consumer markets.

LD59030 belongs to ST's high-accuracy, ultra-low-I_Q LDO family targeting battery-powered applications where minimal quiescent current, fast transient response, and small form factor are critical design constraints.

FAQ

What is the minimum input voltage required for regulation at 300 mA load?

The LD59030DTPU25R requires VIN ≥ VOUT + VDROP to maintain regulation. With 2.5 V output and 135 mV typical dropout at 300 mA, minimum VIN is 2.635 V. At worst-case 200 mV dropout (–40 °C to 85 °C), VIN must be ≥2.7 V. Below this, output voltage collapses linearly with input.

Does the thermal pad require electrical connection, and how should it be routed?

Yes - the exposed thermal pad is internally connected to GND and must be soldered to a dedicated PCB copper pour tied to system ground. This provides both thermal dissipation (R_thJA = 140 °C/W) and ESD robustness (1000 V HBM rating). Do not leave it floating or connect to other nets.

Can LD59030DTPU25R operate with a 0.47 µF output capacitor, and what type is recommended?

Yes - the device is stable with 0.47 µF ceramic capacitors, specifically X5R or X7R dielectrics due to their stable capacitance and ESR over temperature. Avoid Y5V or Z5U types. Place C_OUT within 2 mm of OUT and GND pins, with short, wide traces to minimize inductance.

How does the output discharge function behave during shutdown?

When EN is pulled low, the internal discharge MOSFET turns on, connecting VOUT to GND through a 120 Ω on-resistance. This actively discharges the output capacitor, collapsing VOUT within milliseconds depending on C_OUT value - enabling safe power sequencing and preventing back-powering of upstream circuitry.