STMicroelectronics LD56050DPU100R

Overview

LD56050DPU100R from STMicroelectronics is a 1.00 V, 500 mA ultra-low-dropout linear regulator with NMOS pass transistor and dedicated bias supply (VBIAS) pin enabling 80 mV typical dropout at full load. It features logic-controlled shutdown (<0.1 µA standby), active output discharge, thermal shutdown (160 °C), and ±0.5% output accuracy at 25 °C - optimized for space-constrained, battery-powered mobile and camera power rails.

For engineers reviewing the LD56050DPU100R datasheet, LD56050DPU100R pinout, LD56050DPU100R application, or LD56050DPU100R equivalent, key selection considerations include VBIAS voltage compliance (≥VOUT + 1.4 V), DFN4 1.2 × 1.2 mm footprint constraints, output discharge MOSFET behavior, and foldback current limiting under short-circuit conditions.

Technical Context

The LD56050DPU100R employs an NMOS pass element driven by a separate VBIAS rail, decoupling control circuitry from VIN to sustain ultra-low dropout across low input voltages (down to 0.8 V). Its internal architecture integrates a dedicated enable comparator, thermal foldback protection, and a grounded output discharge MOSFET activated during shutdown.

Stability is achieved with minimal external components: a 1 µF X5R/X7R ceramic input capacitor, 100 nF VBIAS bypass, and ≥1.0 µF output capacitor (2.2 µF typical), operating within 3–300 mΩ ESR range. The device maintains ±1.5% output tolerance over –40 °C to +85 °C junction temperature.

Key Specifications

Pinout & Package

LD56050DPU100R is housed in a thermally enhanced DFN4 1.2 × 1.2 mm package (0.45 mm height, 4-pin, exposed thermal pad), compatible with standard reflow profiles and supporting high-density layout in mobile form factors.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B102MR-G and RT9080-10GB, LD56050DPU100R uniquely combines VBIAS-enabled ultra-low dropout, integrated output discharge, and ±0.5% room-temperature accuracy - making it optimal for next-gen mobile and medical edge devices demanding both efficiency and functional safety.

Availability

LD56050DPU100R is available at Aetrix Electronics and suitable for mobile phones, tablets, and battery-powered medical monitors requiring stable component supply, long-lifecycle support, and RoHS-compliant DFN packaging.

Supply support for LD56050DPU100R 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 microcontrollers, power management ICs, and analog/mixed-signal devices for automotive, industrial, and consumer markets.

The LD56050 belongs to ST's high-accuracy, ultra-low-IQ LDO portfolio targeting space- and power-constrained portable electronics - emphasizing dropout performance, thermal robustness, and integration of safety-critical functions like output discharge.

FAQ

Can LD56050DPU100R operate with VIN equal to VOUT?

No. Minimum VIN is VOUT + VDROP, where VDROP is 80 mV typ. at 500 mA. At light loads, dropout drops further (e.g., 27 mV at 150 mA), but VIN must exceed VOUT by at least the specified dropout voltage under operating conditions. Attempting VIN = VOUT will cause regulation loss and potential instability.

What happens if the VBIAS pin voltage falls below specification?

If VBIAS drops below VOUT + 1.4 V (or 2.4 V absolute minimum), the NMOS gate drive weakens, increasing dropout voltage and potentially causing output sag or oscillation. Below the 1.6 V UVLO threshold, the device shuts down entirely. A 100 nF ceramic capacitor must be placed directly at the VBIAS pin to suppress ripple-induced dips.

Is the output discharge function enabled automatically during shutdown?

Yes. When EN is pulled low, the internal discharge MOSFET (RON = 110 Ω) connects VOUT to GND, actively sinking charge from the output capacitor. This occurs regardless of VIN or VBIAS state and completes within milliseconds - eliminating need for external bleed resistors in battery-sensitive designs.

How does thermal shutdown interact with current limiting?

Current limiting (foldback to 365–500 mA at short-circuit) acts first to reduce power dissipation. If junction temperature still rises to 160 °C, thermal shutdown overrides all functions, disabling the pass element. Recovery occurs only after junction cools by 20 °C hysteresis - preventing thermal cycling during marginal overload conditions.