MAX809REUR

MAX809REUR is an 8‑pin microprocessor supervisor (reset IC) from Maxim Integrated (now Analog Devices). It monitors Vcc and asserts an active-low reset to a microcontroller whenever supply voltage falls below a fixed threshold, then releases reset after the voltage stabilizes with a built-in delay. The REUR suffix denotes the device variant in a Pb-free, tape-and-reel package.
Key points:
- Fixed thresholds (common options include 4.63 V for 5V logic and 2.93 V for lower-voltage systems; check the exact MAX809REUR rating in the datasheet).
- No external components required; clean power-on reset with internal hysteresis for noise immunity.
- Low quiescent current and a defined reset release delay.
- Output suitable for driving the MCU reset line.
Applications:
- MCU reset generation in 3.3V/5V systems, embedded controllers, and battery-powered devices.
Usage:
- Connect Vcc to the IC’s Vcc pin, GND to ground, and route the reset output to the MCU’s reset pin. The IC asserts reset when Vcc is too low and releases it once Vcc stabilizes.
For exact Vth, pinout, and electrical specs, consult the MAX809REUR datasheet.

MAX809REUR is a fixed-threshold voltage supervisor for microprocessors. Key features (variant-dependent; check exact threshold version):
- Fixed Vcc threshold versions (e.g., ~2.9V, 3.0V, 3.3V, 4.63V, etc) for different rail voltages
- Automatic power-on reset: asserts reset while Vcc is below threshold and for a defined time after Vcc rises
- Manual reset input for external forcing of reset
- Push-pull, active-low reset output compatible with TTL/CMOS inputs
- Low quiescent current and suitable for battery-powered designs
- Noise immunity with built-in hysteresis to prevent spurious resets
- Wide operating temperature range; RoHS/lead-free package options
Note: exact features and threshold are version-specific. The REUR suffix indicates a particular package/lead-free variant; verify the datasheet for the precise thresholds and electrical characteristics.

MAX809REUR comes in a SOT-23-3 (3-pin) package, RoHS-compliant.

MAX809REUR is a 3-pin microprocessor supervisory/reset IC (SOT23-3). It monitors Vcc and provides a reset signal to a microcontroller. The RESET output (active-low) is asserted when the supply falls below the device’s fixed threshold and is released after Vcc stabilizes. No external components are required. Pins: Vcc, GND, RESET (output).

Manufacturer: Maxim Integrated Products (the MAX809 family originated with Maxim).
What kind of company: Maxim Integrated is a semiconductor company that designs and manufactures analog and mixed‑signal integrated circuits (including voltage supervisors and power-management ICs). In 2020, Maxim was acquired by Analog Devices, so the product line is now under Analog Devices.

- MCU/processor reset supervision during power-up/down
- Brown-out/power-fail protection for digital systems
- Battery-powered/portable devices needing reliable, low-quiescent-reset signals
- Automotive and industrial control circuits requiring deterministic reset on supply changes
- Embedded systems, data loggers, and communications equipment needing a clean reset reference

Equivalent devices (voltage supervisors/reset ICs) from other vendors that match MAX809REUR's function:
- TI TLV803/TLV803B (fixed thresholds such as 2.93V, 4.63V)
- TI TPS3839 (reset supervisor)
- Microchip MCP1316/MCP1317 (voltage supervisors)
- Analog Devices ADM803/ADM803A (reset supervisor)
Note: choose parts with the same threshold, reset polarity, and timeout. Provide your supply voltage and required reset delay for precise matching.