µP Reset Circuits with Capacitor-Adjustable Reset/Watchdog Timeout Delay

Active: In Production.

The MAX6746–MAX6753 low-power microprocessor (µP) supervisory circuits monitor single/dual system supply voltages from 1.575V to 5V and provide maximum adjustability for reset and watchdog functions. These devices assert a reset signal whenever the V_CC supply voltage or RESET IN falls below its reset threshold or when manual reset is pulled low. The reset output remains asserted for the reset timeout period after V_CC and RESET IN rise above the reset threshold. The reset function features immunity to power-supply transients.

The MAX6746–MAX6753 have ±2% factory-trimmed reset threshold voltages in approximately 100mV increments from 1.575V to 5.0V and/or adjustable reset threshold voltages using external resistors.

The reset and watchdog delays are adjustable with external capacitors. The MAX6746–MAX6751 contain a watchdog select input that extends the watchdog timeout period by 128x. The MAX6752/MAX6753 contain a window watchdog timer that looks for activity outside an expected window of operation.

The MAX6746–MAX6753 are available with a push-pull or open-drain active-low RESET output. The MAX6746–MAX6753 are available in an 8-pin SOT23 package and are fully specified over the automotive temperature range (-40°C to +125°C).

Download Rev 6 (PDF, 176kB) E-Mail