一种高精度双环反馈的新型过流保护电路
High accurate self-recovering and dual-loop feedback over-current protection circuit

采用环路开关进行电路控制，与传统过流保护电路相比，可控电流源形成的输入偏置电压使其具有更好的鲁棒性，从而保证过流保护电路的精度. 同时，三极管动态输出阻抗构成的开关能够让输出电压在轻重负载切换时具有自恢复能力. 仿真结果表明，启动过流保护电路的电流阈值误差被控制在10%以内，有效提高了过流保护电路的精度，实现了输出电压的自恢复功能.
The circuit is controlled by a loop switch. The input bias voltage provided by the controllable current source makes the circuit have better robustness than traditional over-current protection circuit. The switch constituted by the output dynamic impedance of transistor makes the output voltage self-recovery in light load and heavy load switching. The results of simulation in HUAHONG 0.35 μm BCD technology show that the error of current threshold of the over-current protection circuit is within 10%. The over-current protection circuit effectively improves the accuracy and achieves self-recovery function of the output voltage