Maxim Integrated MAX823MEUK+T Microprocessor Supervisory Circuit

The Maxim Integrated MAX823MEUK+T is a highly reliable microprocessor (µP) supervisory circuit designed to monitor power supplies and microprocessor activity in digital systems. It provides excellent circuit reliability and low cost by eliminating external components and adjustments when used with 5V-powered circuits.

This supervisory circuit ensures that the µP and its peripherals are reset properly during power-up, power-down, and brown-out conditions. The MAX823MEUK+T features a standard reset threshold voltage of 4.63V, making it ideal for 5V power supply monitoring. In addition to the reset output, the device includes a manual reset input that allows the user to initiate a system reset.

The reset output of the MAX823MEUK+T is active-low and is guaranteed to be in the logic low state for VCC down to 1V. This ensures that the µP is held in reset until the supply voltage reaches a stable operating level. The reset signal remains active for a minimum of 140ms after VCC rises above the reset threshold level, providing adequate time for the system to stabilize.

With its small 5-pin SOT-23 package, the MAX823MEUK+T is designed for space-constrained applications. It consumes low power, with a typical supply current of only 3.5µA, making it suitable for portable and battery-powered equipment. The device also features an immunity to short VCC transients, ensuring reliable operation in noisy environments.

Key features of the MAX823MEUK+T include:

• Precision monitoring of 5V power-supply voltages
• Fully specified over temperature
• 140ms min power-on reset pulse width
• Active-low reset output
• Manual reset input
• Low supply current of 3.5µA (typical)
• Compact 5-pin SOT-23 package

The MAX823MEUK+T supervisory circuit is a critical component for enhancing system reliability in microprocessor-based systems, providing essential monitoring and control functions to safeguard system integrity during power fluctuations and system resets.