STMicroelectronics LD39015M10R

Overview

LD39015M10R from STMicroelectronics is a 150 mA ultra-low-noise, low-quiescent-current LDO voltage regulator with fixed 1.0 V output, 80 mV typical dropout at 100 mA, ±2.0% output accuracy at 25 °C, and stable operation with 1 µF ceramic output capacitor. It features logic-controlled shutdown (EN pin), operates from 1.5–5.5 V input, and targets battery-powered portable electronics requiring clean, efficient power.

For engineers reviewing the LD39015M10R datasheet, LD39015M10R pinout, LD39015M10R application, or LD39015M10R equivalent, key selection criteria include its 18 µA no-load quiescent current, 29 µVRMS output noise without bypass cap, thermal/short-circuit protection, SOT23-5L package footprint, and enable-controlled OFF-mode current <1 µA.

Technical Context

The LD39015M10R implements a bandgap-referenced feedback loop with internal trimming for 1.0 V output, using a PMOS pass transistor to achieve ultra-low dropout. Its EN pin directly controls an internal bias network to disable regulation and reduce supply current below 1 µA.

Stability is guaranteed with 1 µF ceramic output capacitors across the full load range (0–150 mA) and temperature range (−40 °C to +125 °C); PSRR is 65 dB at 1 kHz and rolls off above 10 kHz. Internal thermal shutdown activates at 160 °C with 20 °C hysteresis.

Key Specifications

Pinout & Package

SOT23-5L surface-mount package: 2.95 mm × 1.60 mm × 1.30 mm body, 0.95 mm pitch, lead-free and RoHS-compliant per ECOPACK® specifications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B102MR-G and RT9013-10GB, the LD39015M10R delivers superior noise performance (29 vs. ≥45 µVRMS), lowest dropout (80 mV), and industry-leading shutdown current (<1 µA), making it optimal for ultra-low-power, noise-sensitive, and thermally constrained designs.

Availability

LD39015M10R is available at Aetrix Electronics and suitable for wearable health monitors, Bluetooth LE sensor nodes, industrial wireless transmitters, and smart card reader modules requiring stable component supply, long-lifecycle support, and consistent parametric performance.

Supply support for LD39015M10R 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 silicon solutions for automotive, industrial, and consumer markets since 1987.

The LD39015 series belongs to ST's high-efficiency, ultra-low-noise LDO portfolio, engineered specifically for battery-powered portable and IoT edge devices demanding minimal quiescent power and clean regulated rails.

FAQ

What is the minimum input voltage required for regulation at 1.0 V output?

The LD39015M10R requires a minimum input voltage of 1.1 V to maintain regulation (1.0 V + 80 mV typical dropout). However, functional operation begins at VIN = 1.45 V (UVLO turn-on threshold), and absolute minimum rated input is 1.5 V per datasheet specifications. Below 1.5 V, performance is not guaranteed.

Can the LD39015M10R operate without an output capacitor?

No. The device requires a minimum 1 µF ceramic output capacitor for stability across all load and temperature conditions. Omitting COUT causes oscillation and potential damage; the 29 µVRMS noise specification assumes COUT = 1 µF. ST specifies stability within the region defined in Figure 7 of the datasheet.

Is the NC pin (Pin 4) safe to connect to ground?

Pin 4 is internally not connected and must remain electrically floating. Grounding it violates the SOT23-5L layout recommendation in ST's datasheet (Section 7.1) and may compromise thermal performance or ESD robustness. It should be left unconnected on PCB or covered with solder mask.

How does the EN pin behave during power-up sequencing?

The EN pin has a logic-threshold of 0.9 V (min) for activation and 0.4 V (max) for deactivation. During VIN ramp-up, EN must exceed 0.9 V after VIN reaches 1.45 V to ensure clean start-up; if EN rises before VIN, the device remains in UVLO until input stabilizes. External RC filtering is recommended for noisy enable sources.