【摘要】 提出了一种新颖的电流模降压型DC-DC变换器的电流采样电路。该电路结合传统电流采样电路的优点,合理地使用LDMOS,实现了宽电压大负载应用DC-DC变换器的电感电流的精确采样。该结构在一款0.35μm BCD工艺的降压型DC-DC变换器中进行了投片验证。仿真和测试结果表明,输入电压为4.75 V~25 V、负载为0 A~3 A的情况下,DC-DC变换器芯片输出稳定,纹波较小且瞬态特性良好。更多还原

【Abstract】 A novel current-sensing circuit for current-mode DC-DC converters is presented. The inductor current of DC-DC converters used under wide voltage and heavy load is accurately sensed by the proposed circuit which combines the advantages of traditional current-sensing circuits and uses LDMOS properly. The proposed structure has been used in a buck DC-DC converter and it has been fabricated in a 0. 35 μm BCD process. The performance is verified by simulation and test. With a4. 75 ~ 25 V supply voltage range and a 0 ~ 3 A load range,the DC-DC converter works steadily,and it also has a small ripple voltage and a good transient response.更多还原