The DS1232 MicroMonitor™ Chip monitors three vita l conditions for a microprocessor: power supply, software execution, and external override. First, a precision temperature-compensated reference and comparator circuit monitors the status of Vcc . When an out-of-tolerance c ondition occurs, an internal power fail signal is generated which for ces reset to the active state. When Vcc returns to an in-tolerance condition, the reset signals are kept in the active state for a minimum of 250 ms to allow the power supply and processor to stabilize.
The second function the DS1232 performs is pus hbutton reset control. The DS1232 debounces the pushbutton input and guarantees an active reset pulse width of 250 ms minimum. The third function is a watchdog timer. The DS1232 has an internal timer that fo rces the reset signals to the active state if the strobe input is not driven low pr ior to timeout. The watchdog timer f unction can be set to operate on timeout settings of approximately 150 ms, 600 ms, and 1.2 seconds.
