APW7078a1APW7078PreliminarySingle PWM Switching ControllerFeatures Wide operating voltage:1.8V to 5.5V Adjustable frequency: maximum 1MHZ Incorporates soft-start function Built-in short-circuit detection circuit(SCP) Low operating current: maximum to 200uA Minimized peripheral components Package: SO8, TSSOP8General DescriptionThe APW7078 is a single PWM, step-up DC-DC controller with low minimum operating voltage application integrating soft-start, phase compensation, sawtooth wave oscillator and short circuit detection function. And the oscillator switching frequency on chip can be operated by terminating OSC pin to connect capacitor and resistor for adjustable operating frequency. Softstart is adjusted with external capacitor, which sets the input current ramp. Besides, the external……