Maxim Integrated MAX6390XS29 Microprocessor Reset Circuit

The Maxim Integrated MAX6390XS29 is a high-quality, precision microprocessor (µP) supervisory circuit designed to monitor power supplies in digital systems. It provides excellent circuit reliability and low cost by eliminating external components and adjustments when used with +2.5V to +5.0V-powered circuits.

This compact supervisory circuit ensures that the µP and its associated peripherals are reset properly during a power failure or brownout condition. The MAX6390XS29 is optimized for operation with a nominal supply voltage of 2.9V, making it ideal for low-voltage applications. It features a factory-trimmed reset threshold, which ensures accurate monitoring of the VCC supply voltage without the need for external resistors.

The device boasts a significant feature: an active-low RESET output, which remains asserted for a minimum of 140ms after VCC has risen above the reset threshold level. This provides ample time for the system to stabilize before the processor is allowed to run. The reset output is guaranteed to be in the correct state for VCC down to 1.0V, which is particularly beneficial for systems that operate at low voltages.

Another key feature of the MAX6390XS29 is its low supply current of only 1.6µA (typical), which makes it an excellent choice for portable and battery-powered applications where power conservation is critical. The device comes in a small, 4-pin SC70 package, which is ideal for space-constrained applications.

For added flexibility, the MAX6390XS29 also includes a debounced manual reset input. This allows for a manual system reset to be triggered with an external pushbutton, providing designers with a simple and effective way to manually restart the system if necessary.

In summary, the Maxim Integrated MAX6390XS29 is a robust, low-power, and easy-to-use reset circuit that provides reliable monitoring of system voltages, ensuring that microprocessor-based systems remain functional and safe in the event of power disturbances.