Design of a Step-down DC-DC Converter ASIC Applied to Portable Electronic Products
Using CSMC 0.5μm process model, a Step-Down DC-DC converter ASIC applied to portable electronic products was designed. The peak current-mode control PWM with slope compensation was adopted in the power management chip to improve the dynamic response speed of the system; the error amplifier and PWM comparator was redesigned to improve the response speed and stability of the chip; the over-current protection function was included in the peak current sampling circuit; in addition, the circuit with the pulse-skipping mode reduce the battery energy loss. Capable of delivering 600mA Output Current over a wide input voltage range from 3.1 to 5.5V, the ASIC, that has a fixed operation frequency of 800kHz and 95% conversion efficiency, is ideally suited for portable electronic products. No external Schottky diode is required in practical application.