STMicroelectronics STM1810MWX7F

Overview

STM1810MWX7F from STMicroelectronics is a low-power, active-low push-pull reset supervisor IC designed to monitor +5 V supply rails in microcontroller-based systems. It asserts reset when VCC drops below 4.37 V (typ.), maintains reset for ≥100 ms after recovery, and operates down to VCC = 1.0 V over –40 °C to +105 °C - enabling reliable power-up sequencing and brownout protection in industrial embedded controllers.

For engineers reviewing the STM1810MWX7F datasheet, STM1810MWX7F pinout, STM1810MWX7F application, or STM1810MWX7F equivalent, key selection criteria include guaranteed reset assertion at low VCC, factory-trimmed 4.37 V threshold accuracy (±2.5%), 4 µA typical supply current, SOT23-3 footprint compatibility, and direct interface with MCU reset inputs without external pull-ups.

Technical Context

The STM1810MWX7F implements a precision voltage reference and comparator to continuously monitor VCC against a fixed 4.37 V (typ.) reset threshold. Its internal timer ensures minimum 100 ms reset pulse width (trec) after VCC recovers above threshold, preventing premature MCU release during marginal supply conditions.

It features push-pull active-low RST output capable of sinking 20 mA, operates with no external components, and includes built-in immunity to fast VCC transients - rejecting negative glitches ≤20 µs at 100 mV overdrive - making it suitable for noisy industrial power environments.

Key Specifications

Pinout & Package

SOT23-3 package (WX suffix), 3-pin small outline transistor outline with gull-wing leads; moisture sensitivity level MSL3; RoHS-compliant and ECOPACK® certified.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar reset supervisor applications.

Compared with MAX809TRD3T and TPS3808G33DBVR, STM1810MWX7F uniquely combines 4.37 V precision threshold, 100 ms fixed delay, 4 µA typical current, and documented 20 µs transient immunity - making it optimal for cost-sensitive, noise-prone 5 V industrial control designs requiring minimal BOM count.

Availability

STM1810MWX7F is available at Aetrix Electronics and suitable for industrial PLC controllers, smart energy meters, automotive body control modules, and medical infusion pump controllers requiring stable component supply, long-term lifecycle support, and consistent parametric performance.

Supply support for STM1810MWX7F 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.

STM181x is ST's low-power reset supervisor product line targeting space-constrained, high-reliability embedded systems requiring precise voltage monitoring and deterministic reset timing without external components.

FAQ

What is the exact reset threshold voltage for STM1810MWX7F?

The STM1810MWX7F has a factory-trimmed typical reset threshold of 4.37 V, with ±2.5% accuracy over the full operating temperature range (–40 °C to +105 °C). This value is specified in Table 3 of the official STMicroelectronics datasheet (Doc ID11464 Rev 8) and applies to all units marked "MWX7F", confirming its designation for 5 V supply monitoring.

Does STM1810MWX7F require an external pull-up resistor on the RST pin?

No. STM1810MWX7F features a push-pull active-low output and drives the RST pin directly without external components. Unlike open-drain variants (e.g., STM1811), it sources and sinks current internally - eliminating the need for a pull-up resistor and simplifying PCB layout in 5 V MCU reset circuits.

Can STM1810MWX7F operate reliably during fast VCC transients?

Yes. The device rejects negative-going VCC transients up to 20 µs duration when the overdrive is 100 mV below the reset threshold, as verified in Figure 19 of the datasheet. This immunity is achieved via internal comparator hysteresis and filtering, making it suitable for noisy 5 V rails in industrial motor drives and power supplies.

Is STM1810MWX7F compatible with microcontrollers that have bidirectional reset pins?

No - STM1810MWX7F uses a push-pull output and is not designed for bidirectional reset interfaces. For MCUs with bidirectional RST pins (e.g., some STM32 or PIC devices), open-drain variants like STM1811MWX7F or STM1816MWX7F are required to avoid bus contention; STM1810MWX7F should only be used with standard active-low input reset pins.