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设计了一种应用于峰值电流型控制Buck DC-DC转换器的分段式斜坡电流补偿电路,以消除峰值电流控制模式下可能产生的次谐波振荡.该电路采样峰值电流,通过采样电阻将电流转换为电压输出.当开关脉冲控制的导通时间占空比D＜35％时,斜坡补偿电压的斜率为零.当占空比D＞35％时,斜坡补偿电压的斜率占空比变化.斜坡补偿电路不仅消除了D＞50％时次谐波振荡引起的系统不稳定现象,还提高了电源芯片的带载能力.基于0.5 μm BCD工艺进行设计,仿真结果显示,该斜坡补偿电路具有良好的补偿能力和带载能力.应用该电路的DC-DC转换器的最高负载工作电流达到7A.“,”A piecewise slope current compensation circuit which was applied to buck DC-DC converter with peak current controlling was design to eliminate the on-chip sub-harmonic oscillation that could be generated in the peak current controlling mode.The proposed compensation circuit sampled the peak current and converted the current to output voltage through the sampling resister.When the duty cycle (D) of turn-on time controlled by the switched pulse was smaller than 35％,the gradient of slope compensation voltage was zero.However,when the D was larger than 35％,the gradient of slope compensation voltage was varied with the D.Not only the system instability that caused by the sub-harmonic oscillation when the D was larger than 50％ had been eliminated effectively,but also the load capacity of power supply circuit chip had been improved.The circuit was designed in a 0.5 μm BCD process.The simulation results showed that the proposed circuit had good performances such as current compensation ability and load capacity.The load current of the DC-DC converter,in which the slope compensation circuit was applied,was up to7 A.