CS8151

 5V ±2% / 100 mA Output Voltage
Micropower Compatible Control Functions:
      WAKE UP
      WATCHDOG
      RESET 
Low Dropout Voltage: 400mV @ 100mA
 Low Sleep Mode Quiescent Current (400µA typ)
 Protection Features:
        Thermal Shutdown
        Short Circuit
        74V Load Dump
        Reverse Transient (-50V)

Power Dissipation....................................................................Internally Limited
Output Current (V_OUT, RESET , WAKE UP)...............................Internally Limited
Reverse Battery...........................................................................................-15V
Maximum Load Dump Transient ..................................................................+74V
Maximum Negative Transient (t<2ms) .........................................................-50V
ESD Susceptibility (Human Body Model).........................................................2kV
ESD Susceptibility (Machine Model)..............................................................200V
Logic Inputs/Outputs .......................................................................-0.3V to +6V
Storage Temperature Range.......................................................-55 to +150
Lead Temperature Soldering
    Wave Solder (through hole styles only) .....................10 sec. max, 260 peak
Reflow (SMD styles only) ...........................60 sec. max above 183, 230 peak

The CS8151 is a precision 5V, 100mA micro-power voltage regulator with very low quiescent current (400µA typical at 200µA load). The 5V output is accurate within ±2% and supplies 100 mA of load current with a typical dropout voltage of 400mV. Microprocessor control logic includes Watchdog, Wake Up and RESET. This unique combination of low quiescent current and full microprocessor control makes the CS8151 ideal for use in
battery operated, microprocessor controlled equipment.

The CS8151 WAKE UP function brings the microprocessor out of Sleep mode. The microprocessor in turn, signals its WAKE UP status back to the CS8151 by issuing a WATCHDOG signal.

The WATCHDOG logic function monitors an input signal (WDI) from the microprocessor. The CS8151 responds to the falling edge of the WATCHDOG signal which it expects at least once during each wake-up period. When the correct WATCHDOG signal is received, a falling edge is issued on the wake-up signal line.

RESET is independent of VIN and operates correctly to an output voltage as low as 1V. A RESET signal is issued in any of three situations. During power up the RESET  is held low until the output voltage is in regulation. During operation if CS8151 output voltage shifts below the regulation limits, the RESET toggles low and remains low until proper output voltage regulation is restored. And finally, a RESET signal is issued if the regulator does not receive a WATCHDOG signal within the WAKE UP period.

The RESET pulse width, WAKE UP signal frequency, and WAKE UP delay time are all set by one external capacitor C_Delay.

The regulator is protected against short circuit, over voltage, and thermal runaway conditions. CS8151 can withstand 74 volt load dump transients, making it suitable for use in automotive environments.