The XCL205/XCL206/XCL207 series is a synchronous step-down micro DC/DC converter which integrates an inductor and a control IC in one tiny package (2.5mmx2.0mm, H=1.0mm). A stable power supply with an output current of 600mA is configured using only two capacitors connected externally. Operating voltage range is from 2.0V to 6.0V. Output voltage is internally set in a range from 0.8V to 4.0V in increments of 0.05V. The device is operated by 3.0MHz, and includes 0.42P-channel driver transistor and 0.52N-channel switching transistor. As for operation mode, the XCL205 series is PWM control, the XCL206 series is automatic PWM/PFM switching control and the XCL207 series can be manually switched between the PWM control mode and the automatic PWM/PFM switching control mode, allowing fast response, low ripple and high efficiency over the full range of loads (from light load to heavy load). During stand-by, the device is shutdown to reduce current consumption to as low as 1.0A or less. With the built-in UVLO (Under Voltage Lock Out) function, the internal driver transistor is forced OFF when input voltage becomes 1.4V or lower. XCL205B/XCL206B/XCL207B series provide short-time turn-on by the soft start function internally set in 0.25 ms (TYP). XCL205B(C) /XCL206 B(C) / XCL207B(C) integrate CL auto discharge function which enables the electric charge stored at the output capacitor CL to be discharged via the internal auto-discharge switch located between the LX and VSS pins. When the devices enter stand-by mode, output voltage quickly returns to the VSS level as a result of this function.