STMicroelectronics STM6822ZWY6F

Overview

STM6822ZWY6F 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 3.3 V power supplies, provides active-low open-drain RST output, delivers 1.4 ms reset pulse width (typ.), guarantees RST assertion down to VCC = 1.0 V, and draws only 3 µA supply current (typ.) - enabling reliable power-on reset and fault recovery in low-power microcontroller applications.

For engineers reviewing the STM6822ZWY6F datasheet, STM6822ZWY6F pinout, STM6822ZWY6F application, or STM6822ZWY6F equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative parts - all grounded in ST's production datasheet DocID11110 Rev 14.

Technical Context

The STM6822ZWY6F implements a precision bandgap voltage reference and comparator to monitor VCC against a fixed 3.3 V threshold (±2.5% over temperature), asserting reset when undervoltage occurs. Its internal watchdog timer triggers reset if WDI remains static for ≥1.6 s (typ.), and clears on any WDI edge transition.

Reset assertion is sustained for trec (1.4 ms typ.) after VCC recovery, MR release, or watchdog timeout. The open-drain RST output requires an external pull-up resistor and sinks up to 20 mA, supporting level-shifting across supply domains up to 6 V.

Key Specifications

Pinout & Package

STM6822ZWY6F is housed in a standard 5-pin SOT23-5 package (JEDEC MO-178AB), with 1.3 mm height, 2.9 mm × 1.6 mm footprint, and gull-wing leads compatible with automated PCB assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM6822ZWY6F, STM6823ZWY6F simplifies layout by eliminating the pull-up resistor but sacrifices bus-sharing flexibility, while TPS3808G33DBVR trades critical features (MR, short reset pulse, open-drain) for lower cost in non-interactive applications.

Availability

STM6822ZWY6F is available at Aetrix Electronics and suitable for industrial PLC controllers, smart metering modules, medical handheld diagnostics, and automotive body control modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for STM6822ZWY6F 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 silicon solutions for automotive, industrial, and embedded markets with emphasis on reliability, efficiency, and integration.

STM6xxx is ST's dedicated microprocessor supervisor product line, engineered for deterministic reset generation, robust watchdog supervision, and seamless integration into resource-constrained embedded systems across industrial and automotive applications.

FAQ

What is the function of Pin 3 (RST) on STM6822ZWY6F?

Pin 3 is the active-low open-drain reset output. When asserted, it sinks current to ground; it requires an external pull-up resistor to a valid logic-high voltage (up to 6 V). This configuration enables wired-OR reset buses and level translation between different supply domains, unlike push-pull variants which drive high/low actively.

Can the watchdog timer be disabled on STM6822ZWY6F?

Yes - the watchdog timer is disabled when the WDI pin (Pin 1) is left unconnected or driven by a tristated output. In that state, internal leakage (<10 µA) and capacitance (<200 pF) must remain within limits. No configuration register or external signal is required; disabling is purely hardware-based via WDI pin state.

What is the minimum VCC required for STM6822ZWY6F to assert a valid reset?

The device guarantees functional reset assertion down to VCC = 1.0 V across the full industrial temperature range (–40 °C to +85 °C). Below this voltage, internal circuitry may not operate reliably, but the RST output remains asserted as long as VCC stays below the 3.3 V threshold, even during deep brownout.

How does the MR pin interface with a mechanical push-button?

The MR pin has an internal 52 kΩ pull-up resistor, so connecting a normally open momentary switch between MR and GND creates a fully functional manual reset. No external components are needed. For noisy environments, a 0.1 µF capacitor from MR to GND adds immunity without affecting reset timing.