STMicroelectronics LDL212PU15R

Overview

LDL212PU15R from STMicroelectronics is a fixed-output 1.5 V, 1.2 A low-dropout linear regulator IC with 350 mV typical dropout at full load, 87 dB PSRR at 120 Hz, and operation from 2.5 V to 18 V input. It features enable control, undervoltage lockout, and thermal/current/power protection-designed for post-regulation in DC-DC converters and noise-sensitive analog rails in industrial and consumer systems.

For engineers reviewing the LDL212PU15R datasheet, LDL212PU15R pinout, LDL212PU15R application, or LDL212PU15R equivalent, this page delivers verified electrical specs, package-specific pin mapping (SO-8/DFN6), thermal performance data, and real-world use cases in SMPS secondary regulation and point-of-load power delivery.

Technical Context

The LDL212PU15R implements a bandgap-referenced error amplifier driving a PMOS pass transistor, enabling stable regulation with minimal dropout and high PSRR across 120 Hz–100 kHz. Its internal UVLO triggers at 2.4 V with 200 mV hysteresis, and enable logic transitions between 0.4 V (low) and 1.2 V (high) over temperature.

Thermal shutdown activates at 175 °C with 25 °C hysteresis; current limiting engages at 1.5–2 A short-circuit threshold. The device supports both fixed (1.5 V) and adjustable variants via dedicated SENSE/ADJ pin configuration, with output accuracy of ±2% at 25 °C and ±3% over –40 °C to 125 °C.

Key Specifications

Pinout & Package

LDL212PU15R is available in SO-8 batwing plastic micropackage and DFN6 (3x3 mm and 2x2 mm). All packages share identical pin functionality but differ in thermal resistance: SO-8 (θ_JA = 55 °C/W), DFN6 (3x3) (θ_JA = 55 °C/W), DFN6 (2x2) (θ_JA = 65 °C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with TSM10915TR and LP5907MFX-1.5/NOPB, LDL212PU15R uniquely combines 1.2 A drive, 350 mV dropout, full protection set, and enable control in a thermally robust SO-8/DFN6 footprint-making it the sole fit for industrial POE and automotive body control designs requiring reliability at full spec.

Availability

LDL212PU15R is available at Aetrix Electronics and suitable for industrial motor control, automotive body electronics, point-of-load FPGA power, and medical sensor signal chain applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LDL212PU15R 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 LDL212 belongs to ST's high-PSRR, low-dropout LDO family engineered specifically for post-regulation in switched-mode power supplies and noise-sensitive analog subsystems-emphasizing ripple rejection, thermal resilience, and functional safety readiness.

FAQ

What is the minimum input voltage required for stable 1.5 V output at 1.2 A?

The LDL212PU15R requires VIN ≥ VOUT + VDROP(MAX) = 1.5 V + 0.6 V = 2.1 V per datasheet Table 4, but absolute minimum operating VIN is specified as 2.5 V. At 1.2 A and 25 °C, typical dropout is 350 mV, so 1.85 V input sustains regulation-however, 2.5 V is the guaranteed operational floor across temperature and process variation.

Can LDL212PU15R be used without an output capacitor?

No. The device requires a minimum 4.7 µF ceramic output capacitor with ESR ≤100 mΩ for stability, as confirmed in Figure 30 (stability plan) and Section 3 "Typical application". Omitting COUT causes oscillation and potential damage due to phase margin loss in the internal control loop.

Is the SENSE pin on LDL212PU15R configurable for external feedback?

No. LDL212PU15R is a fixed-output variant-the SENSE pin is internally connected to VOUT and must be externally shorted to VOUT per datasheet Note 1. External resistor dividers are invalid; only adjustable versions (e.g., LDL212PUR) support programmable VOUT via ADJ pin.

How does thermal performance differ between SO-8 and DFN6 (2x2) packages?

SO-8 has θ_JA = 55 °C/W and θ_JC = 20 °C/W; DFN6 (2x2) has θ_JA = 65 °C/W and θ_JC = 15 °C/W. While DFN6 offers lower junction-to-case resistance, its higher junction-to-ambient value means greater PCB temperature rise at 1.2 A-SO-8 is preferred for high-power density layouts with limited copper area.