Design Of Control And Driving Circuits For High-side Power Switch

Power integration industry is an important field of electronics manufacturing industry. Many power integrated circuit(PIC) have been developed. With the development of integrated circuits and widely used for airborne drive, automotive electronics, aviation, household appliances and other fields. High-side power switch, one of the PIC typical applications, plays an important role in its application for intelligent control and protection of power output.The main contribution of this paper is to design a driving and control circuit which can apply to High-side power switch and realizes fully functional with other protect circuits. Driving circuit includes regulator and charge pump. And regulator is a voltage converter which convert high input voltage 4.7V~52V to 5V logic voltage for low voltage modules. Charge pump is a direct driving circuit of power switch and guarantees that gate voltage always 5V higher than the power supply and 1.8A working current. Control circuit which processing all of the protective signal is a logic circuit inside the chip. It realizes intelligent control of power switch working state and avoid chip destroyed by abnormal condition, such as high voltage or high current. Simulation results are given to ensure the parameters to satisfy the specification.The high-side power switch of this paper is designed based on 0.35μm BCD process platform, and its layout design based on the PDK provided by FAB. High voltage LDMOS which is used for power switch has to support high voltage and high current and also be required low resistance(200mΩ). It is the main focus of layout design. The operating voltage of high-side power switch would change across wide range. It is necessary to isolate high-voltage module and low-voltage module to avoid breakdown of low-voltage device. Finally, package design is given.