一种带自适应电荷泵的超低功耗NMOS LDO

An Ultra-Low Power NMOS LDO with Adaptive Charge Pump

设计了一种带自适应电荷泵的超低功耗快速瞬态响应NMOS LDO,电路主要包含误差放大器、缓冲器、功率级、动态零点模块以及自适应电荷泵模块。该自适应电荷泵能够根据负载电流的大小调节工作频率,在兼顾大负载条件下功率管栅极需求的同时,保证了轻载下超低功耗的需求。同时为了满足电路中快速瞬态响应的需要,加入了动态电流电路。电路基于0.18μm BCD工艺设计,其工作电压范围为2.5~3.6 V,输出电压为1.2 V,负载范围为10μA~20 mA,工作的温度范围为-40~125℃。仿真结果显示,所设计的LDO供电电压调整率可达到1.123 mV/V,重载跳轻载时的恢复时间和轻载跳重载时的恢复时间分别为260μs和5μs,而静态电流最小仅为0.291μA。

An ultra-low power fast transient response NMOS LDO with adaptive charge pump was designed.The whole circuit mainly included an error amplifier module,a buffer module,a power stage,a dynamic zero module and an adaptive charge pump module.The adaptive charge pump could adjust the operating frequency according to the size of the load current.It ensured the ultra-low power consumption under light load conditions while taking into account the requirements of the gate of the power transistor under heavy load conditions.At the same time,in order to meet the needs of fast transient response in the circuit,a dynamic curent circuit was added.The circuit was designed in a BCD 0.18μm process.Its working voltage range is 2.5-3.6 V,the output voltage is 1.2 V,the load range is 10μA-20 mA,and the working temperature range is-40-125℃.The simulation results show that the designed LDO power supply voltage regulation rate can reach 1.123 mV/V,the recovery time of heavy load jumping to light load and the recovery time of light load jumping to heavy load are 260μs and 5μs respectively,while the minimum quiescent current is only 0.291μA.