一种基于COT控制的快速瞬态响应Buck变换器

A Fast Transient Response Buck Converter Based on COT Control

设计了一种基于TSMC 0.18μm CMOS工艺的快速瞬态响应Buck型变换器。基于电流模COT架构的Buck型变换器,结合电容电流采样电路和负载电流调节器,设计了一种新颖的瞬态增强电路,对负载电流进行补偿,有效地减小了恢复时间,提高了输出电压精度。仿真结果表明,没有瞬态增强电路时,负载电流从0 A跳变到3 A,电流变化率为3 A/10 ns,下跌电压为166.9 mV,恢复时间为5.8μs;加入瞬态增强电路后,下跌电压变为21 mV,恢复时间变为0.5μs。没有瞬态增强电路时,负载电流从3 A跳变到0 A,电流变化率为3 A/10 ns,过冲电压为73 mV,恢复时间为3.3μs;加入瞬态增强电路后,过冲电压变为36 mV,恢复时间变为0.6μs。

A buck converter with fast transient response was designed in TSMC 0.18μm CMOS process.The buck converter based on the current mode COT architecture was combined with the capacitive current sampling circuit and the load current regulator,and a novel transient enhancement circuit was designed.The transient enhancement circuit compensated the load current,effectively reduced the recovery time and improved the output voltage accuracy.The simulation results show that without the transient enhancement circuit,when the load current jumps from 0 A to 3 A,the current change rate is 3 A/10 ns,the undershoot voltage is 166.9 mV,and the recovery time is 5.8μs.After adding the transient enhancement circuit,the undershoot voltage becomes 21 mV,and the recovery time becomes 0.5μs.Without the transient enhancement circuit,when the load current jumps from 3 A to 0 A,the current change rate is 3 A/10 ns,the overshoot voltage is 73 mV,and the recovery time is 3.3μs.After adding the transient enhancement circuit,the overshoot voltage becomes 36 mV,and the recovery time becomes 0.6μs.