摘要
针对DC-DC变换器中脉冲宽度调制产生的谐波振荡问题,基于斜坡补偿原理,提出一种随占空比变化的分段线性斜坡补偿电路,以克服单一斜率斜坡补偿容易造成斜坡过补偿的问题。Pspice仿真结果表明,输出的波形与理论分析相符,系统在电感电流发生扰动的情况下具有稳定的输出电压。采用Active-Semi的专利ISOBCD20工艺进行流片,测试结果表明,电路在420kHz开关频率下产生高达2A的输出电流,芯片可以在高达20V的输入电压下工作。在关断模式下仅消耗8μA的电流,具有很高的工作效率,峰值效率达到95%。
To overcome harmonic oscillation resulted from pulse width modulation in DC-DC converter,a piecewise linear slope compensation circuit changing with duty cycle was designed based on slope compensation,which also solved the problem of excessive slope compensation due to single slope compensation.PSpice simulation results showed that output waveform of the circuit was coincided with theoretical analysis.Stable output voltage was achieved in case of inductor current disturbance.The circuit was fabricated based on Active-Semi＇s patent technology ISOBCD20.Test results showed that the circuit could output current up to 2 A at 420 kHz switching frequency,and the chip could work at 20 V input voltage.Consuming only 8 μA of current in shutdown mode,the circuit achieved a peak efficiency up to 95%.
出处
《微电子学》
CAS
CSCD
北大核心
2012年第5期659-663,共5页
Microelectronics
