Document
Rev.2.0
SMALL PACKAGE PFM CONTROL STEP-UP SWITCHING REGULATOR
S-8321/8322 Series
The S-8321/8322 Series is a CMOS PFM-control step-up switching regulator which mainly consists of a reference voltage source, an oscillation circuit, a power MOS FET, and a comparator. The new method PFM control circuit automatically switches the duty ratio according to load, offering products of low ripple over a wide range, high efficiency, high output current. A step-up switching regulator is constructed by externally connecting only a coil, a capacitor and a diode to the S-8321/8322 Series. This feature, along with its small package and low current consumption, makes the S-8321/8322 Series ideal for the power supply of portable equipment. A built-in protection circuit prevents damage to the IC by turning off the MOS FET when the voltage at CONT pin exceeds the limit during ON of the built-in MOS FET. For applications requiring a high output current, products used with an external transistor are also .