Design Of A High-performance Bicmos Charge-pump Power Management Chip

The advent of a worldwide energy crisis prompted people to find a variety of ways to improve energy efficiency. Power Management IC is such an effective equipment which can manage electric current distribution and conversion power. PWM switching power supply more than 500mA load current circumstances has a very good conversion results. Charge pump converter can apply to small-size electronic devices which load current between 10mA to 500mA,therefore,A high performance BICMOS charge-pump power management chip design will present in this paper.based on the principles of 2 times charge-pump converter,we have designed the Circuit System according functional requirements and performance indicators. The main circuit modules included bandgap,overheat protection circuit, oscillation circuit, comparator circuit and control circuit.This project focusing on the design of the bandgap and Thermal protection circuit module based on BiCMOS process. Simulation results for bandgap show that the output voltage of bandgap is 1.24V, the temperature coefficient of 6.68ppm/℃, PSRR of 82dB. Thermal protection circuits ensure that the chip turn-off when he chip temperature higher than 150℃,and the system returned to normal work when the temperature dropped to 130℃. Then we have designed other functional modules and overall circuit, analysis and simulation. simulation results show that the ripple voltage is less than 30mV at tt,ff,ss 3 kinds of mode, and the output voltage of chip is stable for the 5V when input voltage change between 2.7V to 5.5V,the average conversion efficiency of 83%.Finally we have completed layout of overall circuit,the chip area is 780×460μm2, layout passed DRC and LVS verification.