The MIC705, MIC706, MIC707, and MIC708 areinexpensive microprocessor supervisory circuits that monitor power supplies in microprocessor-based systems. The circuit functions include a watchdog timer, microprocessor reset, power-failure warning, and a debounced manual reset input. The MIC705 and MIC706 offer a watchdog timer function while the MIC707 and MIC708 have an active-high reset output in addition to the active-low reset output. Supply voltage monitor levels of 4.65V and 4.4V are available. The MIC705 and MIC707 have a nominal reset threshold level of 4.65V while the MIC706 and MIC708 have a 4.4V nominal reset threshold level. When the supply voltage drops below the respective reset threshold level, /RESET is asserted.