View xc9110 xc9111-series datasheet:

XC9110/XC9111 Series ETR0406 004 PFM Controlled Step-Up DC/DC Converter / Controller ICs ■GENERAL DESCRIPTION The XC9110/9111 series is a group of PFM controlled step-up DC/DC converter/controller ICs designed to generate low supply voltage by the combination of PFM control and CMOS structure. The series is ideal for applications where a longer battery life is needed such as in portable communication equipment. With a built-in 2.5ΩN-channel driver transistor, the XC9110A/C/E and XC9111A/C/E types provide a step-up operation by using only a coil, a capacitor, and a diode connected externally. The XC9110/9111B, D and F versions can be used with an external transistor for applications requiring larger currents. Output voltage is internally programmable in a range from 1.