Research And Design Of PWM Current-Mode Controller XDJ6303

This paper is based on the project of research institute of electronic CAD Theoretical research and design of key technique for high-performance mix-signal IC ,And it mainly deals with the design process and working principle of PWM current-mode controller.Firstly, this paper discussed the percept of chip's system design and the requirement of process, and then realized the model circuits according to the working frequency of the circuit; overheat protection and reducing EMI and so on. Simultaneously, it explained the working process considering the working condition. Finally, the low dissipationpower, high-voltage resistance power PWM current-mode controller for universal off-line supplies featuring stangby and short circuit protection was completed.The chip XDJ6303 adopted the steady current-mode. The switch-off time was dictated by the peak current setpoint. This component represented the ideal candidate where low part-count was the key parameter, so the loss was smaller, particularly it was used to low-cost AC/DC adapters, auxiliary supplies etc. Due to its high-performance SMARTMOS high-voltage technology, the circuit incorporates all the necessary components normally needed in conventional mode equipment based supplies: timing components, feedback devices, low-pass filter and startup device and so on. XDJ6303 elegantly solves the problem about the fall of dissipationpower by skipping unwanted switching cycles at a user-adjustable power level, to meeting the requirement of lower dissipatinpower of more and more equipment need no-load standby. By ensuring that skip cycles take place at low peak current, the device ensure quit, noise free operation. Finally, an auto-recovery output short-circuit protection (OCP) prevents from any lethal thermal runaway in overload conditions.The design of XDJ6303 is based on the 0.6um BCD process. The simulation and verification of the whole chip have been completed; the result indicates that they meet the demand of function and the index of the technique.