STMicroelectronics ST730M30R

Overview

ST730M30R from STMicroelectronics is a 300 mA, fixed 3.0 V output low-dropout (LDO) linear regulator in SOT23-5L package, featuring ultra-low 5 μA quiescent current at no-load, ±0.5% output voltage accuracy at 25 °C, and operation across -40 °C to +125 °C. It delivers stable post-regulation for battery-backed smoke detectors and electronic meters where standby power efficiency and thermal robustness are critical.

For engineers reviewing the ST730M30R datasheet, ST730M30R pinout, ST730M30R application, or ST730M30R equivalent, key selection criteria include dropout voltage at 300 mA (max 1.2 V), enable logic thresholds (V_IL ≤ 0.35 V, V_IH ≥ 1.2 V), SOA-current limiting behavior versus (V_IN – V_OUT), and stability with 0.47 µF ceramic output capacitors.

Technical Context

The ST730M30R implements a bandgap-referenced op-amp control loop with internal bias generator and thermal feedback. Its current-limit protection is dynamically scaled with input-output differential voltage to constrain power dissipation under overload, while thermal shutdown activates at ~160 °C with 20 °C hysteresis.

It supports both fixed-output (3.0 V) and adjustable configurations via the ADJ pin (NC in this variant), enabling remote sensing. The enable pin provides hard shutdown with sub-1 µA standby current, and the regulator remains stable with low-ESR ceramic capacitors as small as 0.47 µF on the output.

Key Specifications

Pinout & Package

SOT23-5L surface-mount package (3.0 × 1.6 mm footprint, 1.45 mm height), RoHS-compliant and ECOPACK® certified.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B302MR-G and AP7361-C30W5-7, the ST730M30R uniquely combines 28 V input tolerance, SOA-based current limiting, and 20 °C thermal hysteresis - making it the only option qualified for safety-critical, wide-input industrial and automotive after-market use cases.

Availability

ST730M30R is available at Aetrix Electronics and suitable for smoke detector certification, smart meter production, and industrial sensor node deployment requiring stable component supply across extended temperature and long-lifecycle programs.

Supply support for ST730M30R 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 ST730 series belongs to ST's high-reliability LDO portfolio targeting ultra-low-power, wide-input industrial and safety-critical applications - emphasizing quiescent current optimization, thermal resilience, and fault-safe operation.

FAQ

What is the minimum output capacitor required for stability with ST730M30R?

The ST730M30R requires a minimum 0.47 µF ceramic capacitor (X5R/X7R dielectric) on the VOUT pin to ensure control-loop stability across temperature and load. ESR must remain between 5 mΩ and 500 mΩ over the full operating range. Larger values improve transient response but do not compromise stability.

Can ST730M30R be used with a 12 V automotive battery input?

Yes - ST730M30R supports up to 28 V DC input, making it compatible with 12 V automotive systems including cold-crank (down to 2.5 V) and load-dump transients. Its SOA current limiting and thermal shutdown protect against sustained overloads common in vehicle environments.

Does ST730M30R require an input capacitor, and what value is recommended?

A minimum 0.1 µF ceramic input capacitor is mandatory and must be placed adjacent to the VIN pin. ST recommends using a low-ESR X5R/X7R type; higher values (e.g., 1–10 µF) improve ripple rejection and transient response during fast load steps, especially with long PCB traces.

How does the enable (EN) pin behave during power-up and shutdown?

The EN pin is active-high with logic thresholds of ≤0.35 V (low) and ≥1.2 V (high). It features internal pull-down; however, floating is strictly prohibited. During startup, V_EN must exceed 1.2 V before regulation begins. In shutdown, quiescent current drops to ≤1 µA, and VOUT discharges through the load.