| Central processing unit (CPU) is the heart of modern electronic systems, and then DC power is the heart of CPU. With IC design upgrading and semiconductor processes continuing development, more and more function are integuated in the modern CPU, the internal structure of CPU gets more complex, its power consumption is also growing huge, and then the requirement for power growing more and more rigorous, which makes the chip structure and function of DC power conversion for CPU more complex. Therefore, the research of application based on DC/DC power conversion circuits for CPU is significant. The system theory and testing research about the high-power, two-phases, Buck DC/DC synchronous- rectified switch-converter circuits are done.The methods and procedures of large-scale analog IC design --"Meet-in-middle" is proposed in this dissertation. Using the Verilog-AMS hardware description language, the high level behavior model of an analog IC module can be set up. Then with the "Top-down" approach, the functional module division and large-scale analog IC system design can be implemented. With the "Down-top" approach, the transistor-level circuits of the analog module divided can be achieved. The new design method can effectively accelerate the progress of large-scale analog integrated circuit design and the complete certification of the system simulation.On the base of the VRM9.0 DC power converters design standards and the analysis on DC switching conversion circuit principles, the performance and work principles of analog IC modules is studied in depth. Using the high level hardware description language—Verilog-A, the behavior models of analog switch, differential operation amplifier, band-gap voltage reference, digital-to-analog converter, voltage detection and level shift circuit are built, and then these models are simulated for function certification. Based these behavior models, the system design of a high-power, two-phases, Buck DC/DC synchronous- rectified switch-converter is implemented. By the simulation of the system design certification, the functional modules of the system are divided, and the parameters concerned of these modules are obtained. This results can guide further transistor-level circuit design.On the base of the models of these various functional modules, the a transistor-level circuits of those are designed. By analyzing the operation principles of these modules, a novel high performance CMOS band-gap voltage reference with wide voltage output using the techniques for temperature compensation and resistive subdivision is proposed in the thesis. The output of the band-gap voltage reference ranges from 0.20V to 1.25V and temperature coefficient is very low. A novel high accuracy RC oscillator is proposed in the thesis. By using the error-amp to improve the period delay, the period accuracy of this oscillator can be improved by 30% in the same process. Using thermometer decoding structure, a 5-bit high-precision DAC converters circuit is achieved. The output voltage changes from 1.10V-1.85V with 25mV of step-length, and the output error is about±1%, less than 0.25LSB differential nonlinear error, nonlinear error about 0.5LSB. According VRM9.0 DC power converters design standards, the power voltage detection circuit, the output voltage control circuit, and the over current and over voltage protection circuits are designed.The current of the two parallel Buck converters can be shared excellently by using the auto average output current method as well as the output voltage droop method. Detecting the output current and output voltage at the same time, the current feedback and the voltage feedback control the loop at same time, by which, the transient response rate of the switch-conversion is improved and the accuracy of output current and voltage is enhanced. In sampling the output current, since the large output current and the small conduct-resistance of the synchronous rectified MOSFET, the sense resistance is replaced by the conduct-resistance of the synchronous rectified MOSFET to improve the conversion efficiency. By using the "hiccup" mode over current protection, the misoperation is effectively prevented due the supply voltage fluctuation. On the base of the analysis of operation principles of high-power and synchronous rectified DC/DC switch-converter, the external element parameters are identified. The entire transistor-level circuit is simulated with the Spice model parameters provided by manufacturer and in the Star-Sim? certification tools.The physical layout design of the two-phase Buck synchronous rectified DC/DC controller and the dual channel MOSFET driver are implemented respectively in SinoMOS 0.8μm DPDM CMOS process and SinoMOS 0.8μm DPDM High-voltage (40V) BiCMOS process. The PCB test board is designed according to the package of the two chips, and the electrical parameters test of the whole system is completed. At the setting of 1.85V output voltage and load resister 47mΩ, the currents of the parallel Buck converters are shared each other. The average output current of one channel is about 20A, the whole output current of the system is about 40A. The test results proved the correction of the circuits design.
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