STMicroelectronics LDK220M-R

Overview

LDK220M-R from STMicroelectronics is an adjustable low-dropout linear regulator (LDO) delivering up to 200 mA output current with 100 mV typical dropout at 100 mA, 2.5–13.2 V input range, ±2.0% output voltage accuracy at 25 °C, and logic-controlled shutdown enabling <1 µA off-mode current. It supports ceramic output capacitors as low as 1 µF and operates across –40 °C to 125 °C for battery-powered and industrial power rail regulation.

For engineers reviewing the LDK220M-R datasheet, LDK220M-R pinout, LDK220M-R application, or LDK220M-R equivalent, key selection criteria include its ultra-low quiescent current (55 µA typ.), integrated output discharge function, EN-controlled enable/disable timing, and compatibility with multiple compact packages including SOT23-5L, SOT323-5L, SOT-89, and DFN6-1.2×1.3.

Technical Context

The LDK220M-R implements a bandgap-referenced error amplifier driving a PMOS pass transistor, enabling low dropout and stable regulation under load transients. Its internal bias generator ensures consistent operation across temperature and input voltage variations.

It features dual protection mechanisms: constant-current short-circuit limiting and thermal shutdown with 160 °C trip point and 20 °C hysteresis. The ADJ pin allows external resistor-divider configuration for output voltages from 1.2 V to 12 V in 100 mV steps, while the EN pin provides precise logic-level control of output state and automatic VOUT discharge when pulled low.

Key Specifications

Pinout & Package

LDK220M-R is available in four surface-mount packages: SOT23-5L (2.95 × 1.60 mm), SOT323-5L (2.0 × 2.1 mm), SOT-89 (4.5 × 2.45 mm), and DFN6-1.2×1.3 mm. Pin functions vary by package; the SOT-89 variant omits the ADJ and EN pins and is fixed-output only.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B332MR-G and ADM7172ACPZ-3.3-R7, the LDK220M-R uniquely combines adjustable output, EN control, integrated discharge, and sub-1 µA shutdown - making it optimal for compact, battery-aware, and multi-rail embedded systems requiring flexible voltage configuration.

Availability

LDK220M-R is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, set-top box USB peripherals, and laptop embedded controller rails requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LDK220M-R 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, sensors, and analog components for industrial, automotive, and consumer markets.

The LDK220 series belongs to ST's high-efficiency, low-quiescent-current LDO family - engineered specifically for battery-constrained and thermally demanding applications where minimal dropout, noise, and standby power are critical.

FAQ

What output voltage range does LDK220M-R support?

The LDK220M-R is the adjustable version of the LDK220 family and supports output voltages from 1.2 V to 12 V in 100 mV increments, set using an external resistor divider between OUT, ADJ, and GND. The ADJ pin voltage is regulated to 1.185 V ±2% at 25 °C, enabling precise ratio-based scaling.

Can LDK220M-R operate with a 1 µF ceramic output capacitor?

Yes - the LDK220M-R is explicitly designed for stability with 1 µF ceramic capacitors (X5R/X7R) on the output, as confirmed in Table 6 and Figure 22 of DS10219. This eliminates the need for larger, higher-ESR electrolytic or tantalum capacitors and reduces PCB area and cost.

How does the output discharge function work, and what is its resistance?

When the EN pin is driven low, the LDK220M-R activates an internal 18 Ω discharge path from OUT to GND, actively pulling down the output voltage. This prevents residual charge from back-powering downstream circuitry and ensures safe, controlled power-down sequencing - critical for USB and hot-swap applications.

Is thermal shutdown recoverable, and what is its hysteresis?

Yes - thermal shutdown is fully auto-recovering. The device shuts down at 160 °C junction temperature and resumes normal operation once the die cools by 20 °C (hysteresis), i.e., below 140 °C. This behavior is verified in Table 6 and prevents oscillation during sustained thermal overload conditions.