带可调跳周期功能的峰值电流比较器电路设计

为了降低待机状态下的功率消耗和可听噪声，开关电源可切换至可调跳周期模式。文章首先介绍了可调跳周期的传统实现方案及其局限性，然后提出了一种可实现可调跳周期模式功能的峰值电流比较器电路，仅需要一个芯片引脚和一个比较器就能实现上述两种功能，大大减小了电路面积，节约了设计成本。此外，在电路内部还增加了上升沿隐匿(LEB)电路，增强了电路设计的可靠性。最后给出具体电路并进行深入分析，并得出HSPICE仿真结果，证明达到设计目标。

The Design of A Current Sense Comparator Combined With The Programmable Skipping Cycle Mode

Switched mode power supplies (SMPS) may turn to work in a programmable skipping cycle mode for low standby loss and acceptable audible noise. The paper first introduces the conventional method for implementing a programmable skipping cycle mode and its disadvantage. Then a design of a current sense comparator combined with the programmable skipping cycle mode is developed. The two functions are programmed without using additional pin and comparator , which reduces the cost and size. Furthermore, the LEB circuit is designed to insure the stability. Finally, a detailed analysis of the factual circuit is given, and its performance has been verified by HSPICE simulation.