STMicroelectronics LDL212DR

Overview

LDL212DR from STMicroelectronics is a high-PSRR, low-dropout linear regulator IC supporting adjustable output voltages from 1.18 V to VIN − VDROP(MAX), delivering up to 1.2 A with typical dropout of 350 mV at full load. It operates across 2.5 V–18 V input, features enable control and undervoltage lockout, and is used in DC-DC post-regulation and SMPS secondary-side filtering.

For engineers reviewing the LDL212DR datasheet, LDL212DR pinout, LDL212DR application, or LDL212DR equivalent, this page delivers verified electrical specs, package mapping (SO-8/DFN6), thermal performance data, and real-world use cases in point-of-load regulation and industrial power sequencing.

Technical Context

The LDL212DR implements a precision bandgap reference and error amplifier driving a PMOS pass transistor, enabling stable regulation with minimal headroom. Its internal current, thermal, and safe-operating-area (SOA) protections operate autonomously without external components.

It supports two configurations: fixed-output versions (e.g., LDL212PU33R) and the adjustable LDL212DR, where the ADJ pin sets VOUT via resistor divider feedback. The EN pin provides logic-level shutdown with sub-1.5 µA off-state current at 18 V input.

Key Specifications

Pinout & Package

LDL212DR is available in SO-8 batwing plastic micropackage, DFN6 (3×3) mm, and DFN6 (2×2) mm packages. All variants feature an exposed thermal pad requiring GND connection for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and ADM7172ACPZ-R7, LDL212DR uniquely balances 1.2 A capability, 18 V input tolerance, integrated UVLO, and 350 mV dropout - making it optimal for ruggedized point-of-load regulation where both current and input voltage margins are critical.

Availability

LDL212DR is available at Aetrix Electronics and suitable for industrial PLCs, automotive infotainment systems, and medical sensor modules requiring stable component supply across extended temperature and voltage ranges.

Supply support for LDL212DR 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 devices for industrial, automotive, and consumer markets.

LDL212DR belongs to ST's high-PSRR LDO family engineered specifically for noise-sensitive post-regulation in switched-mode power supplies and demanding industrial environments.

FAQ

What output capacitor value and ESR are required for stability with LDL212DR?

ST specifies 4.7 µF minimum ceramic output capacitance with ESR ≤100 mΩ at 100 kHz for all packages. Figure 30 and 31 in DS11245 show stable regions: for 5 V output, C_OUT ≥4.7 µF and ESR ≤22 mΩ; for adjustable version, C_OUT ≥4.7 µF and ESR ≤10 mΩ ensures phase margin >45° across temperature and load.

Can LDL212DR be used with input voltage below 2.5 V?

No. Absolute maximum ratings specify 2.5 V minimum operating input voltage. Below this, regulation fails and VOUT drops nonlinearly - confirmed by Figure 16 showing VDROP rise above 600 mV at VIN <2.5 V and IOUT=1.2 A. UVLO also disables operation below 2.3 V turn-on threshold.

How does the ADJ pin function in fixed-output variants versus LDL212DR?

In LDL212DR (adjustable), ADJ is the feedback node connected to a resistor divider between VOUT and GND. In fixed-output versions (e.g., LDL212PU33R), the SENSE pin (pin 8 in SO-8, pin 2 in DFN6) must be shorted to VOUT - it is not a true ADJ pin but a dedicated output sense path for improved load regulation.

Is thermal pad connection mandatory for DFN6 packages?

Yes. The exposed thermal pad in both DFN6 (2×2) and DFN6 (3×3) packages must be soldered to a dedicated GND copper pour with ≥4 thermal vias (0.3 mm diameter) to inner GND planes. Omitting this increases θ_JA by >30 °C/W, risking thermal shutdown at 800 mA load in still air.