Dc-dc Switching Power Supply Chip Technology Research

Single-chip switching power supply management Integrated Circuit (IC) has many virtues such as high integration level, most cost effective, lowest component count switcher solution, and high performance. Its being used can form high efficiency insulated switching power supply without using utility power transformer. The switching power IC is selected firstly in the design of high power switching power supply, precision switching power supply, application specific switching power supply and so on in the world, which has been making switching power supply short, small, light and thinThe control techniques of DC-DC switching converters are completely described and analyzed. The techniques with two different methods are classified as: the mode of pulse width modulated, and the difference of control signal. The advantages and disadvantages of each method is analyzed and compared, and where each method is more adapted to is pointed out.A type of switching power supply management IC based on Current mode control method is designed which is a PWM boost converter. The basic principle, system structure is analyzed and studied intently. The small-signal models for the switching converters based on current mode control are deducted. System stability and the principle of slope compensation which is used to improve system stability also discussed. Simulation results validate the usefulness of the slope compensation. In the meantime, the all sub-circuits are also designed and emulated carefully including inverter, RS type flip-flop, voltage reference circuit, error amplifier, voltage comparator, sawtooth-wave generator, PWM comparator, Soft activation circuit and so on. As a result, all of the sub-circuits answer the requirements. This chip has taped out with the 0.5um mix-signal process of csmc. The test results show that it works very well.Another type of switching power supply management IC is designed which is a PFM buck converter. Basic principle, system structure and sub-circuits of it are discussed briefly. This chip also taped out successfully based on the 3um BCD process of bsmc.