Inverting Micro DC-DC with Integrated Coil
The new XCL301 series is the first Torex micro dc-dc converter that supports a negative voltage output. The XCL301 inverting micro dc-dc converter integrates a P-channel FET, an inductor and a control IC.
The operating voltage range is 2.7V to 5.5V, and the output voltage is fixed at -3.3V (±2.0%) and the output current is 50mA. The XCL301 is designed to generate a negative output rail for op amps, LCD, CCD and AOC applications.
An inverted output dc-dc circuit can be configured by simply adding two external ceramic capacitors and a Schottky diode and as the XC301 itself only measures 2.5mm x 2.0mm x 1.00mm, the complete circuit is small and simple, saving board space and development time.
The XCL301 series uses automatic PFM/fixed off time PWM. In automatic PFM/fixed off time PWM control, the IC operates by PFM control when the load is light to achieve high efficiency over the full load range from light to heavy.
The device provides a stable inverting power supply to be configured using only a SBD and two capacitors connected externally. It has a quiescent current of 40µA.
During stand-by, all circuits are shutdown to reduce current consumption to as low as 0.1µA (typical) or less. With the built-in UVLO (Under Voltage Lock Out) function, the internal P-channel MOS driver transistor is forced OFF when input voltage becomes 2.2V or lower.
The XCL301's CL High Speed discharge function enables the electric charge at the output capacitor CL to be discharged via the internal discharge.