The NCV8518A device is a precision micropower voltage regulator. It has a fixed output voltage of 5.0 V and regulates within ±2%.Microprocessor control logic includes an active RESET (with DELAY), wakeup, watchdog and enable.The NCV8518A Wakeup function brings the microprocessor out of Sleep mode. The microprocessor in turn signals its Wakeup status back to the NCV8518A by issuing a Watchdog signal.The active RESET circuit operates correctly at an output voltage as low as 1.0 V. The RESET function is activated during the power up sequence, during normal operation if the output voltage drops below the regulation limits or if the regulator does not receive a Watchdog signal within a Wakeup period.The Watchdog logic function monitors an input signal (WDI) from the microprocessor. The device responds to the falling edge of the Watchdog signal which it expects at least once during each Wakeup period.Enable is a standard TTL and CMOS logic compatible input that can be used to turn the regulator on or off. In the disabled/shutdown state, the pass transistor is off and total quiescent current is less than 1 µA.Also encompassed in this device are safety features such as thermal shutdown and short circuit protection, an important consideration in automotive environments.NCV8518A is pin for pin compatible with NCV8518 and can replace this device in any new design.