STMicroelectronics STLQ020C33R

Overview

STLQ020C33R from STMicroelectronics is a 3.3 V fixed-output, 200 mA ultra-low-quiescent-current LDO voltage regulator in SOT323-5L package, operating from 2 V to 5.5 V input, delivering 160 mV dropout at full load, ±2% output accuracy at 25 °C, and 300 nA typical quiescent current at no load. It serves as a precision power rail for image sensors and wearable healthcare devices requiring extended battery life.

For engineers reviewing the STLQ020C33R datasheet, STLQ020C33R pinout, STLQ020C33R application, or STLQ020C33R equivalent, key selection criteria include its 300 nA no-load I_q, 160 mV dropout at 200 mA, EN-controlled shutdown (5 nA off-state), thermal/overcurrent protection, and compatibility with 1 µF ceramic input/output capacitors.

Technical Context

The STLQ020C33R employs an adaptive biasing circuit that maintains ultra-low quiescent current while enabling fast transient response and 52 dB PSRR at 100 Hz (V_OUT = 2.5 V, 10 mA load). Its internal bandgap reference and CMOS-compatible enable logic support precise voltage regulation across –40 °C to +125 °C ambient.

Dropout behavior is actively managed: quiescent current remains controlled even in dropout conditions, and thermal shutdown activates at 160 °C (20 °C hysteresis) only when load exceeds 1 mA-ensuring stability during light-load standby without false triggering.

Key Specifications

Pinout & Package

SOT323-5L package: 1.8 × 2.1 mm footprint with exposed pad connected to GND; optimized for space-constrained portable PCBs and compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B332MR-G and ADP160AUJZ-3.3-R7, STLQ020C33R uniquely balances 200 mA capability, 300 nA no-load I_q, 160 mV dropout, and full-temperature thermal protection-making it optimal for space- and battery-limited portable medical and imaging systems.

Availability

STLQ020C33R is available at Aetrix Electronics and suitable for smartphone image sensor power, wearable PPG monitoring, and portable healthcare device designs requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for STLQ020C33R 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 STLQ020 series belongs to ST's ultra-low-I_q LDO portfolio, engineered specifically for battery-powered portable electronics where multi-year standby life and minimal voltage droop under dynamic load are critical system requirements.

FAQ

What is the minimum input voltage required for STLQ020C33R to maintain regulation?

The STLQ020C33R requires VIN ≥ VOUT + VDROP to regulate. With VOUT = 3.3 V and typical dropout = 160 mV at 200 mA, minimum VIN is 3.46 V under full load. At lighter loads (e.g., 1 mA), dropout drops to 15 mV, allowing regulation down to 3.315 V. The absolute minimum specified VIN is 2 V-but regulation is only guaranteed above dropout threshold.

Can STLQ020C33R be used with ceramic output capacitors smaller than 1 µF?

No. The datasheet specifies a minimum 1 µF X5R/X7R ceramic capacitor with ESR between 3 mΩ and 500 mΩ for loop stability. Capacitors below 1 µF risk oscillation or poor transient response, especially under load steps. Larger values (e.g., 2.2 µF) are acceptable if ESR remains within range and capacitance tolerance is maintained across temperature.

Is the NC/ADJ pin on STLQ020C33R required to be grounded?

No. Pin 4 (NC/ADJ) is not internally connected in the fixed 3.3 V version (STLQ020C33R) and may be left floating per ST's recommendation. However, grounding it improves EMI immunity and mechanical robustness in high-vibration environments. Do not connect to any active signal or voltage source.

Does STLQ020C33R provide output discharge functionality?

Output discharge is optional and implemented only in specific versions marked with "D" suffix (e.g., STLQ020C33RD). The STLQ020C33R does not include this feature. If active discharge is required, select the "D" variant or add an external MOSFET-based discharge circuit controlled by the EN signal.