TPS3618

The TPS3617 and TPS3618 are battery-backup supervisors that monitor 5 V supplies. TPS3617 and TPS3618  provide a battery-backup function ideal for applications thatrequire data retention of CMOS RAM during fault conditions. When the voltage at V_DD drops below a preset threshold (V_IT), the active low push-pullRESET output asserts, and V_OUT switches from V_DD (td) expires. During power on, RESET is asserted when the supply voltage (V_DD or V_BAT) goes higher than 1.1 V.

The PFI and PFO pins are provided if additional  voltage monitoring is needed. If the voltage at PFI is less than 1.15 V, the push-pull PFO pin will assert low. When the voltage at PFI exceeds the threshold voltage, PFO will go high These devices also feature a watchdog timer pin (WDI) that monitors processor activity and asserts  RESET if the the processor is inactive longer than the watchdog timeout period. If the watchdog timer is not used, the WDI pin should be left floating. The TPS3617 and TPS3618 are available in an 8-pin  MSOP package and are characterized for operation over a temperature range of -40°C to 85°C.