STMicroelectronics STM6824MWY6F

Overview

STM6824MWY6F from STMicroelectronics is a 5-pin precision voltage supervisor IC with integrated watchdog timer and manual reset input, designed for microprocessor reset management in industrial embedded systems. It monitors VCC at 3.3 V (±2.5%), asserts active-low push-pull RST for ≥1.4 ms, features 1.6 s watchdog timeout, and guarantees reset assertion down to VCC = 1.0 V - enabling reliable power-on reset and fault recovery in programmable logic controllers and motor control drives.

For engineers reviewing the STM6824MWY6F datasheet, STM6824MWY6F pinout, STM6824MWY6F application, or STM6824MWY6F equivalent, key selection criteria include its dual reset outputs (RST and RST), low 3 µA supply current, SOT23-5 package compatibility, and guaranteed operation across –40 to +85 °C industrial temperature range.

Technical Context

The STM6824MWY6F implements a precision bandgap reference and comparator to monitor VCC against a fixed 3.3 V threshold (±2.5% over temperature). Its reset logic asserts RST (active-low push-pull) and RST (active-high push-pull) simultaneously upon VCC dropout, MR low pulse, or WDI timeout - with reset deassertion delayed by trec (1.4 ms typ.) after VCC recovery or MR release.

Watchdog functionality clears on any WDI edge (≥50 ns pulse width) and expires if WDI remains static for ≥1.6 s (typ.). The MR input includes a 52 kΩ internal pull-up, supports TTL/CMOS logic drive, and requires no external debounce - enabling direct connection to momentary switches or microcontroller GPIOs.

Key Specifications

Pinout & Package

STM6824MWY6F is housed in a RoHS-compliant SOT23-5 surface-mount package (2.9 × 1.6 × 1.1 mm), optimized for high-density PCB layouts in space-constrained industrial modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor with watchdog applications.

Compared with MAX6324US33D3+ and TPS3808G33DBVR, STM6824MWY6F uniquely delivers dual complementary reset outputs, lowest quiescent current (3 µA), and industrial-grade temperature support - making it optimal for space- and power-constrained industrial controllers requiring deterministic multi-rail reset coordination.

Availability

STM6824MWY6F is available at Aetrix Electronics and suitable for programmable logic controllers, industrial motor drives, smart energy meters, and factory HMI terminals requiring stable component supply across extended product lifecycles.

Supply support for STM6824MWY6F 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, delivering automotive, industrial, and power management solutions to Tier-1 OEMs and industrial equipment manufacturers.

The STM6xxx family was engineered specifically for robust microprocessor supervision in harsh industrial environments - emphasizing guaranteed reset validity at ultra-low VCC, minimal external components, and seamless integration with legacy and modern MCU reset architectures.

FAQ

What is the function of the WDI pin on STM6824MWY6F?

The WDI (Watchdog Input) pin monitors MCU health by requiring periodic signal edges; if no transition occurs within 1.6 s (typ.), the device asserts RST/RST to force system reset. It accepts TTL/CMOS logic levels, clears on any rising or falling edge ≥50 ns, and draws ≤160 µA when held high - enabling direct connection to any GPIO without buffering.

Can STM6824MWY6F supervise a 5 V supply?

No - STM6824MWY6F is factory-trimmed for 3.3 V ±2.5% threshold detection. While VCC pin accepts 1.0–5.5 V for operation, the reset trigger point remains fixed at 3.3 V. For 5 V supervision, ST offers STM6825MWY6F (5.0 V threshold) or external resistor-divider configurations with compatible variants like STM6321.

How does the MR input behave when left unconnected?

The MR (Manual Reset) input has an internal 52 kΩ pull-up resistor to VCC, so it defaults to logic high when floating. This disables manual reset function - RST/RST remain controlled solely by VCC monitoring and WDI. No external pull-up is needed, and noise immunity is enhanced by adding a 0.1 µF capacitor from MR to GND in electrically noisy environments.

Is STM6824MWY6F pin-compatible with other STM6xxx devices?

Yes - all STM6xxx SOT23-5 variants share identical pinout: Pin 1=WDI, Pin 2=VCC, Pin 3=RST, Pin 4=MR, Pin 5=VSS. However, output types differ: STM6824MWY6F provides active-low and active-high push-pull RST/RST, while STM6321 offers open-drain RST. Direct substitution requires verifying reset output configuration matches system requirements.