高效率高精度开关电源脉宽调制芯片的实现

Realization of pulse width modulation chip for high efficientcy high precision switching regulator

分析了开关电源脉宽调制芯片的实现。提出了一种适用于计算机主板的大电流、高效率、高精度、可编程开关电源脉宽调制芯片的结构。这种芯片结构集成了开关电源的控制、输出调整、输出监控和保护等功能，同时还具有瞬态响应快、启动过冲小、输出电压随输出电流变化波动小等特点。对芯片的主要电路和整个开关电源系统进行了ＨＳＰＩＣＥ模拟，采用１．７μｍＢｉＣＭＯＳ工艺制作了该芯片，并以它为核心建立了一个适用于Ｐｅｎｔｉｕｍ系列主板的开关电源系统。最后对该系统进行了整体性能测试，实验结果完全符合Ｉｎｔｅｌ公司的ＶＲＭ８．１标准。

The realization of pulse width modulation chip for switching regulator is analyzed. An architecture of pulse width modulation chip is proposed, which is suitable for high current, high efficency, high precision and programmable switching regulator on PC mainboard. This chip integrates the control, output adjustment, monitoring and protection function of switching regulator. Its characteristics also include fast transient response, small turn on overshoot, small output voltage fluctuations with output current changes. Major circuits in this chip and the whole DC DC converter system are simulated by HSPICE. The chip is fabricated with 1.7μm BiCMOS process, a switching regulator system based on this chip for Pentium serial PC mainboard is set up. At last, the performance of this system is tested, and the result conforms to Intel VRM8.1 standard.