STMicroelectronics LDK220C-R

Overview

LDK220C-R from STMicroelectronics is a 200 mA adjustable-output low-dropout (LDO) voltage regulator with logic-controlled shutdown, 100 mV typical dropout at 100 mA, ±2.0% output voltage tolerance at 25 °C, and compatibility with 1 µF ceramic output capacitors. It operates from 2.5 V to 13.2 V input and supports industrial temperature range (−40 °C to +125 °C), targeting power management in space-constrained battery-powered systems.

For engineers reviewing the LDK220C-R datasheet, LDK220C-R pinout, LDK220C-R application, or LDK220C-R equivalent, key selection criteria include its ultra-low quiescent current (55 µA typ.), integrated output discharge function, thermal/short-circuit protection, and multi-package availability (SOT23-5L/SOT323-5L/SOT-89/DFN6-1.2×1.3).

Technical Context

The LDK220C-R implements a bandgap-referenced op-amp control loop with internal bias generator and thermal shutdown circuitry (trip point 160 °C, 20 °C hysteresis). Its enable input (EN) provides logic-level shutdown with sub-1 µA off-mode current and active-low output discharge via an internal 18 Ω resistor.

It supports both fixed and adjustable configurations: the "C-R" suffix denotes the adjustable version with ADJ pin, requiring external R1/R2 resistors to set VOUT = VADJ × (1 + R1/R2), where VADJ = 1.185 V (±2%) and IADJ ≤ 1 µA. SOT-89 variant lacks EN and ADJ functionality.

Key Specifications

Pinout & Package

LDK220C-R is available in four thermally optimized packages: SOT23-5L (R_thJA = 160 °C/W), SOT323-5L (246 °C/W), SOT-89 (110 °C/W), and DFN6-1.2×1.3 (237 °C/W). Pin functions vary by package; the SOT23-5L and SOT323-5L share identical pin mapping, while DFN6 and SOT-89 use alternate layouts. SOT-89 omits EN and ADJ pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B332MR-G and ADM7172ACPZ-R7, the LDK220C-R uniquely balances adjustability, ultra-low IQ, and compact packaging-making it optimal for cost-sensitive, battery-operated designs needing flexible output voltage without sacrificing thermal robustness or noise performance.

Availability

LDK220C-R is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, set-top box power rails, and automotive infotainment core logic requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LDK220C-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 devices for industrial, automotive, and consumer markets.

The LDK220 series belongs to ST's high-efficiency, low-noise LDO portfolio engineered specifically for battery-powered and thermally constrained applications demanding precision regulation with minimal quiescent power.

FAQ

What output voltage range can be set using the ADJ pin on LDK220C-R?

The ADJ pin sets VOUT = VADJ × (1 + R1/R2), where VADJ = 1.185 V ±2% at 25 °C. With standard resistor values, outputs from 1.2 V to 12 V in 100 mV steps are achievable. The datasheet confirms VADJ accuracy degrades to ±3% over −40 °C to +125 °C, directly impacting final VOUT tolerance.

Can LDK220C-R operate safely with a 1 µF ceramic output capacitor?

Yes-ST specifies stability with 1 µF ceramic COUT (X5R/X7R) and ESR <1 Ω across all packages. Figure 22 in DS10219 shows the full stable region for COUT (1–22 µF) and ESR (0–10 Ω), confirming 1 µF is well within the recommended zone for noise-sensitive applications.

How does the output discharge function behave during shutdown?

When EN is pulled low, an internal 18 Ω resistor connects OUT to GND, discharging COUT rapidly. ST warns against applying external voltage to OUT during EN = low, as this could damage the discharge transistor. Discharge time for a 1 µF capacitor is ~18 µs (τ = R × C).

Which package offers the best thermal performance for continuous 200 mA operation?

SOT-89 delivers the lowest R_thJA (110 °C/W), enabling highest power dissipation before thermal shutdown. At 200 mA and 1 V dropout (200 mW), junction rise is ~22 °C above ambient-well below the 160 °C trip point. DFN6 (237 °C/W) and SOT23-5L (160 °C/W) require careful layout or derating in sealed enclosures.