STMicroelectronics STM6824RWY6F

Overview

STM6824RWY6F 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 over –40 to +85 °C.

For engineers reviewing the STM6824RWY6F datasheet, STM6824RWY6F pinout, STM6824RWY6F application, or STM6824RWY6F equivalent, key selection criteria include its dual reset outputs (RST and RST), low 3 µA typical supply current, SOT23-5 package compatibility, and guaranteed operation during brown-out conditions below 1.0 V.

Technical Context

The STM6824RWY6F implements a precision bandgap reference and comparator to detect VCC deviations from its 3.3 V threshold (±2.5% over temperature). Its watchdog timer resets on WDI inactivity exceeding 1.6 s (typ.), and clears on any WDI edge-supporting pulse widths as short as 50 ns.

It provides two complementary reset outputs: active-low push-pull RST and active-high push-pull RST, both asserted synchronously during VCC undervoltage, MR activation, or watchdog timeout. The MR input includes a 52 kΩ internal pull-up and supports direct switch-to-ground connection without external debounce.

Key Specifications

Pinout & Package

The STM6824RWY6F is housed in a 5-pin SOT23-5 package (JEDEC MO-178AB), with 0.95 mm pitch, 2.9 mm × 1.6 mm body, and gull-wing leads for reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326UT29D3+ and TPS3808G33DBVR, the STM6824RWY6F uniquely delivers dual-polarity reset outputs, integrated MR with internal pull-up, and guaranteed 1.0 V operation-all in the same compact SOT23-5 footprint-making it optimal for space-constrained industrial controllers requiring robust, flexible reset architecture.

Availability

STM6824RWY6F is available at Aetrix Electronics and suitable for industrial PLCs, smart energy meters, motor drive control boards, and medical handheld diagnostics requiring stable component supply across extended product lifecycles.

Supply support for STM6824RWY6F 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, specializing in microcontrollers, power management, and analog/mixed-signal ICs for industrial, automotive, and consumer markets.

The STM6xxx family was engineered specifically for robust microprocessor supervision in harsh industrial environments, emphasizing brown-out resilience, low-power operation, and ease of integration via minimal external components.

FAQ

What is the exact reset threshold voltage for STM6824RWY6F?

The STM6824RWY6F has a nominal VCC reset threshold of 3.3 V with ±2.5% tolerance over temperature (–40 to +85 °C) and supply voltage range. This is confirmed in Table 6 of the official datasheet (DocID11110 Rev 14), where VRST min = 3.218 V and max = 3.383 V at TA = 25 °C and VCC = 3.3 V.

Can the watchdog function be permanently disabled?

Yes-the watchdog timer is automatically disabled when the WDI pin is left unconnected (floating) or driven by a tristate buffer. In this state, the internal counter is held inactive, and no reset will occur due to watchdog timeout. No configuration register or external component is required.

Does STM6824RWY6F support interfacing with MCUs that have bidirectional reset pins?

Yes-by inserting a 4.7 kΩ series resistor between the RST output and the MCU's bidirectional reset I/O, signal contention is eliminated. This method is explicitly validated in Figure 14 of the datasheet and ensures safe reset assertion regardless of MCU direction state.

What is the maximum capacitive load the RST output can drive?

The RST output is rated for 20 mA sink/source current and maintains valid logic levels driving ≤100 pF total load capacitance (including PCB trace and MCU input capacitance). Driving >100 pF may extend rise/fall times beyond timing specifications, potentially violating MCU reset setup/hold requirements.