The CS8101 is a precision 5V micropower voltage regulator with very low quiescent current (70µA typ at 100µA load). The 5V output is accurate within ±2% and supplies 100mA of load current with a typical dropout voltage of only 400mV. Microprocessor control logic includes an input and an active circuit. This combination of low quiescent current, outstanding regulator performance and control logic makes the CS8101 ideal for any battery operated, microprocessor controlled equipment. The active circuit includes hysteresis, and operates correctly at an output voltage as low as 1V. The function is activated during the power up sequence or during normal operation if the output voltage drops outside the regulation limits by more than 200mV typ. The logic level compatible input allows the user to put the regulator into a shutdown mode where it draws only 20µA typical of quiescent current. The regulator is protected against reverse battery, short circuit, over voltage, and thermal overload conditions. The device can withstand load dump transients making it suitable for use in automotive environments. The CS8101 is functionally equivalent to the National Semiconductor LP2951 series low current regulators.