The R1170 Series are positive voltage regulator ICs by CMOS process. The R1170 Series have features of high ripple rejection, low dropout voltage, high output voltage accuracy, low consumption current. Each of these ICs consists of a voltage reference unit, an error amplifier, resistor net for setting output voltage, a current limit circuit at short mode, a chip enable circuit, and thermal-shunt circuit. Output Voltage of R1170 is fixed in the IC. Low consumption current by the merit of CMOS process and built-in transistors with low ON-resistance make low dropout voltage and chip enable function prolong the battery life. These regulators are remarkable improvement on the current regulators in terms of ripple rejection, input transient response, and load transient response. Maximum Output Current is large for its compact size. Thus, the R1170 Series are suitable for various power sources for portable appliances. Since the packages for these ICs are the SOT-89-5 package or HSON6, high density mounting of the ICs on boards is possible.