STMicroelectronics LDK320AM30R

Overview

LDK320AM30R from STMicroelectronics is a 3.0 V fixed-output, high-accuracy (±0.5% @ 25 °C), low-dropout linear regulator delivering up to 200 mA with 100 mV typical dropout at 100 mA, 88 dB PSRR at 120 Hz, and 60 μA quiescent current - designed for power-sensitive applications in digital still cameras, BD/DVD players, and industrial control modules.

For engineers reviewing the LDK320AM30R datasheet, LDK320AM30R pinout, LDK320AM30R application, or LDK320AM30R equivalent, this page provides verified electrical specifications, SOT23-5L package details, thermal protection behavior, enable-controlled shutdown functionality, and real-world load/line transient performance data - all critical for battery-powered and noise-sensitive 3.3 V rail design.

Technical Context

The LDK320AM30R implements a bandgap-referenced op-amp control loop with internal bias generator and thermal shutdown (160 °C, 20 °C hysteresis). Its architecture supports stable operation with 1 μF ceramic output capacitors and includes logic-controlled EN pin for <1 μA off-mode current.

It integrates short-circuit current limiting (330 mA typ.), SOA protection, and input voltage tolerance from 2.5 V to 18 V. The fixed 3.0 V output version uses no external feedback resistors and excludes the ADJ pin - unlike the adjustable variant - simplifying layout while maintaining ±0.5% initial accuracy and ±1.5% over full temperature range (-40 °C to 125 °C).

Key Specifications

Pinout & Package

SOT23-5L (5-pin small-outline transistor) package with exposed pad for thermal enhancement; footprint compatible with JEDEC MO-178AC standard; suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LDK320M30R, the AM30R offers 3× tighter output accuracy critical for analog-sensing rails; compared with TSM103030TR, it delivers 33% higher current, 13 dB better PSRR, and lower dropout - making it superior for high-fidelity, high-load 3.0 V applications.

Availability

LDK320AM30R is available at Aetrix Electronics and suitable for digital still cameras, Blu-ray players, and industrial PLC I/O modules requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for LDK320AM30R 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 analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The LDK320 series belongs to ST's high-PSRR, low-quiescent-current LDO portfolio - engineered specifically for battery-powered and noise-critical applications where precision, efficiency, and thermal resilience are mandatory.

FAQ

What is the minimum input voltage required for regulation at 3.0 V output?

The LDK320AM30R maintains regulation with input as low as 3.1 V under 100 mA load (100 mV dropout), and down to 3.35 V at full 200 mA load (max 350 mV dropout over temperature). Below 3.1 V, output drops linearly - confirmed by Figure 21 and Table 6 dropout data.

Can the LDK320AM30R be used with a 10 μF ceramic output capacitor?

Yes - the device is stable with 1–22 μF ceramic capacitors (Table 6, Table 7, and Figure 25/26 confirm stability across this range). A 10 μF X7R 0603 ceramic capacitor meets ESR requirements (<1 Ω @ 100 kHz) and improves transient response versus 1 μF.

Does the EN pin require a pull-up resistor?

No - the EN pin has internal pull-down; an external pull-up is only needed if the driving source is open-drain or high-impedance. Logic-high threshold is 1.2 V min (Table 6), and leakage is <100 nA - enabling direct connection to MCU GPIO without additional components.

Is thermal derating required for continuous 200 mA operation in SOT23-5L?

Yes - with R_thJA = 160 °C/W (Table 5), 200 mA at 3.0 V output with 12 V input yields ~1.8 W dissipation, raising junction temperature by ~288 °C above ambient - exceeding 125 °C rating. Derate to ≤120 mA at 12 V input or use forced airflow/heatsinking per thermal guidelines in DS11321 Section 5.