STMicroelectronics STLQ015M33R

Overview

STLQ015M33R from STMicroelectronics is a 3.3 V, 150 mA ultra-low-quiescent-current linear voltage regulator in SOT23-5L package, designed for battery-powered systems requiring extended standby life. It delivers ±2% output voltage accuracy at 25 °C, features 112 mV typical dropout at 150 mA, and supports ceramic output capacitors as low as 1 µF. Its logic-controlled enable pin reduces shutdown current to 1 nA, making it ideal for always-on sensor nodes and portable media players.

For engineers reviewing the STLQ015M33R datasheet, STLQ015M33R pinout, STLQ015M33R application, or STLQ015M33R equivalent, key selection criteria include quiescent current behavior across temperature and load, dropout voltage vs. output current, thermal shutdown threshold (170 °C), and compatibility with low-ESR ceramic capacitors in space-constrained designs.

Technical Context

This LDO employs a P-channel MOSFET pass element with internal reference and error amplifier, enabling stable regulation down to 0.8 V output while maintaining sub-2 µA quiescent current across –40 °C to 125 °C. The enable input directly controls the pass transistor gate via internal logic, ensuring fast turn-on time (160 µs) and true zero-current shutdown mode.

It integrates overcurrent limiting (250–350 mA short-circuit current) and thermal protection with 15 °C hysteresis. Supply voltage rejection reaches 40 dB at 1 kHz (VOUT = 0.8 V) and degrades to 15 dB at 100 kHz, indicating strong low-frequency ripple suppression but limited high-frequency noise immunity.

Key Specifications

Pinout & Package

SOT23-5L is a 5-pin surface-mount plastic package measuring 2.95 mm × 1.60 mm × 1.45 mm (max height), optimized for automated assembly and high-density PCB layouts. Its thermal resistance junction-to-ambient is 255 °C/W, requiring minimal copper area for thermal relief in low-power applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-IQ LDO applications.

Compared with XC6206P332MR and ADP160AUJZ-3.3-R7, STLQ015M33R uniquely balances ultra-low load IQ (1.4 µA), integrated enable control, thermal shutdown, and ceramic-capacitor stability-making it optimal for battery-powered systems requiring both longevity and robustness.

Availability

STLQ015M33R is available at Aetrix Electronics and suitable for wearable health monitors, smart home sensor nodes, industrial PLC I/O modules, and portable medical diagnostic tools requiring stable component supply across multi-year production cycles.

Supply support for STLQ015M33R 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 STLQ series targets ultra-low-power battery-operated applications, emphasizing nanoscale quiescent current, small footprint packaging, and robust protection features for next-generation IoT and portable electronics.

FAQ

What is the minimum input voltage required to maintain 3.3 V output at 150 mA?

The minimum input voltage is determined by dropout: 3.3 V + 112 mV = 3.412 V typical. At worst-case (300 mV dropout, per datasheet Table 4), VIN must be ≥3.6 V. Below this, output voltage collapses linearly with input reduction.

Can STLQ015M33R be used with a 0.47 µF ceramic output capacitor?

Yes-datasheet Table 4 specifies COUT stability range from 0.47 µF to 10 µF. A 0.47 µF X7R 0603 capacitor with ESR between 0.056 Ω and 6 Ω ensures phase margin >45° and avoids oscillation, confirmed in Figure 15's stability region plot.

How does the enable pin behave under partial power-down conditions?

When EN is pulled to GND, the device enters shutdown with 1 nA typical input current. If EN floats or is driven to an undefined voltage (e.g., 0.5 V), the internal logic may not fully disable the pass transistor, causing unpredictable leakage-EN must be actively driven low or high.

Is thermal derating required for continuous 150 mA operation in still air?

Yes-using R_thJA = 255 °C/W, 150 mA at 3.3 V output with 3.6 V input yields ~45 mW dissipation. That produces ΔT = 45 mW × 255 °C/W ≈ 11.5 °C rise above ambient. At 85 °C ambient, junction temperature reaches ~96.5 °C-well below 150 °C max, so no derating needed.