STMicroelectronics LDK220PU27R

Overview

LDK220PU27R from STMicroelectronics is a 2.7 V fixed-output, 200 mA low-dropout linear regulator in DFN6-1.2×1.3 package, featuring 100 mV dropout at 100 mA, ±2.0% output voltage tolerance at 25 °C, 55 µA typical quiescent current, and logic-controlled shutdown with 1 µA off-mode current. It powers core rails in space-constrained battery-powered equipment and set-top boxes.

For engineers reviewing the LDK220PU27R datasheet, LDK220PU27R pinout, LDK220PU27R application, or LDK220PU27R equivalent, key selection criteria include dropout performance at 200 mA load, ceramic-capacitor compatibility (1 µF COUT), thermal shutdown threshold (160 °C), EN pin logic thresholds (0.4 V low / 1.2 V high), and package-specific thermal resistance (RthJA = 237 °C/W for DFN6).

Technical Context

The LDK220PU27R implements a bandgap-referenced op-amp control loop with internal current limiting and thermal protection. Its enable input directly gates the pass transistor bias, enabling fast shutdown (<1 µA total current) and automatic output discharge via an 18 Ω internal resistor when EN is low.

It supports stable regulation with 1 µF ceramic output capacitance across all operating temperatures (–40 °C to 125 °C), and achieves 55 dB PSRR at 120 Hz–1 kHz and 50 dB at 10 kHz-critical for noise-sensitive analog and RF subsystems powered from noisy DC-DC outputs.

Key Specifications

Pinout & Package

LDK220PU27R uses the DFN6-1.2×1.3 package (1.2 mm × 1.3 mm × 0.5 mm height), optimized for thermal performance (RthJA = 237 °C/W) and PCB area efficiency in portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B272MR-G and RT9013-27GB, LDK220PU27R uniquely combines ultra-low dropout (100 mV), integrated output discharge, and full thermal/short-circuit protection in a 1.2×1.3 mm DFN-making it optimal for compact, battery-aware, and thermally constrained designs where reliability under fault conditions is mandatory.

Availability

LDK220PU27R is available at Aetrix Electronics and suitable for battery-powered medical sensors, set-top box USB hubs, industrial PLC I/O modules, and laptop embedded controllers requiring stable component supply with tight voltage tolerance and low-noise regulation.

Supply support for LDK220PU27R 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 power management applications.

The LDK220 series belongs to ST's precision low-noise LDO portfolio, engineered specifically for battery-powered and noise-sensitive systems where ultra-low IQ, fast enable response, and ceramic-capacitor compatibility are mandatory design requirements.

FAQ

What is the minimum input voltage required for LDK220PU27R to regulate 2.7 V output?

The minimum input voltage is 2.8 V - calculated as VOUT + VDROP = 2.7 V + 100 mV (typical dropout at 100 mA). At 200 mA load, dropout rises to 200–350 mV, requiring ≥2.9 V input for guaranteed regulation. Input must stay within absolute max rating of –0.3 V to 14 V.

Can LDK220PU27R be used with a 10 µF aluminum electrolytic output capacitor instead of ceramic?

No - the device is optimized for 1 µF ceramic capacitors (X5R/X7R) with ESR < 100 mΩ. Aluminum electrolytics typically exhibit higher ESR (>1 Ω) and capacitance drift, risking instability and overshoot during load transients. The datasheet explicitly specifies ceramic-only stability.

Is the EN pin 5 V tolerant when VIN = 12 V?

Yes - EN pin voltage rating is –0.3 V to VIN + 0.3 V, so at VIN = 12 V, EN accepts up to 12.3 V. However, logic high threshold is only 1.2 V (min), so standard 3.3 V or 1.8 V GPIO can safely drive it without level shifting.

Does the output discharge function activate automatically when EN goes low, and what is its effective resistance?

Yes - the internal discharge path activates immediately upon EN falling below 0.4 V, pulling VOUT to GND through a nominal 18 Ω resistor. This discharges a 1 µF capacitor in ~12 µs (τ = R×C), ensuring rapid power-down without external components.