Smart Power Ics The Bicyclic Psm Control Circuit Design

Up to now, the normal control mode for smart power integrated circuit (SPIC) has PWM and PFM. PWM bases on CFVW (Constant Frequency Variable Width) control pulse, whereas, PFM bases on CWVF (Constant Width Variable Frequency) control pulse. PWM converter has low efficiency at light loads and high amplitude harmonic. On the other hand, the control circuit and filter for PFM are much complex. PSM (Pulse Skip Modulation) is a novel modulation. This kind of modulation mode operates in constant width and constant frequency mode (CWCF) which differs from the fore both. The work shows that PSM converter could improve its efficiency and suppress EMI. Besides, it processes many advantages, such as good response speed, strong interference rejection, easy to realize, and so on.The author of the dissertation pay a lot efforts to focus on designing the dual-loop control circuit based on optimized PSM, include:1). Researched the relationship of input and output voltage and output valtage ripple, when PSM operate in continuous current mode and discontinuous current mode respectively. What we have done will direct PSM apply to converter.2). Proposed optimized PSM according to the disadvantages of PSM, and researched its stability and the selection of the duty ratio based on the balance theory of energy.3). Designed the dual-loop control circuit based on optimized PSM, which realize to select the suitable duty ratio to make output stable by utilizing voltage and current feedback loops.4). Analysed the relationship of sensor's voltage and LDMOS'voltage, which will benefit from the intergration of high voltage device and low voltage circuit.5). Designed the switching converter system basing on FPGA (including pure PSM algorithm, the PSM algorithm based on state machine and the optimized PSM algorithm), and gave the result of testing and analysis.The dissertation designes the dual-loop control circuit based on optimized PSM,...