A New Load Flow Control The Chip Design

Recently, due to the intrinsic excellent expansibility, reliability and system redundancy for self-repairing, distributed power systems constituted by paralleled and independent power supply modules have had more and more applications. And it brought the rapid development of the load share control technology for paralleled power modules or supplies and attracted more attentions to its improvement. Whithout it the unbalances between load currents of different modules in a paprallel power system will occur and bring about the thermal stress unbalance between them as well. Thus the system will become unstable and even resulted in failure.And some modules will be overloaded even destroyed.In the thesis, a load share IC with the automatic master-slave control (MSC) operation model was suggested based on analysis of the development of the load sharing technique. As it is a typical analog and mixed signal power IC, the special process, BCD (Bipolar-CMOS-DMOS) process, was adapted that was especially suitable for the chips working under high voltage and large current conditions. The IC was accomplished based on this process and various influences were synthetized in the design of its system, circuits, floorplan and layout.The design of some key modules and system as well as the back end design were discussed in details. All these were optimized. The simulation results showed that the performances of the chip met the specifications well. The high stability, reliability and feasibility could be expected and the chip could work properly and efficiently in a wide variation range of ambient temperature and supply voltage fluctuation. Much attention was paid on floorplan and layout design including influence from heat, large current, digital noise and high frequency noise. The chip has been taped-out and tested.Some technical problems have been settled in power IC such as compatibility between digital and analog modules, withstand voltage, etc. The testing results showed that the expected functions and features were realized successfully. Andexperiences in circuit design and layout can be referenced in design of different power management ICs.Test showed that the expected functions were achieved and main features met the requirements well.