一种具有反压保护功能的微功耗LDO

A Micro-Power LDO with Reverse-Voltage Protection

本文提出并实现了一种具有反压保护功能的微功耗LDO.一方面采用新型自适应栅衬偏置技术,使导通管的栅/衬极在输入输出反压状态下自动跟踪输出电压,从而关断导通管沟道,零偏寄生衬漏体二极管,解决了反压状态下LDO的反灌电流和电路闩锁问题.另一方面,稳压环路中综合采用高效双极缓冲技术和零极点抵消频率补偿技术,既解决了微功耗LDO中的环路稳定困难问题,又使漏失电压最小.该款LDO采用BiCMOS工艺实现.测试结果表明,其反向耐压可达9V;负载调整率和线性调整率分别为0.025mV/mA和0.6mV/V;满负载电流(250mA)漏失电压仅为70mV;空载和重载下静态电流分别只有7μA和7.7μA.

In the paper,a Micro-Power LDO with Reverse-Voltage Protection is presented.For the one hand,utilizing a new Self-Adaptive Gate/Bulk Biasing technique,the gate and bulk voltages of the pass transistor can track the output in the case of reverse voltage,which make the channel pinched and the parasitic drain-to-bulk diode zero biased.Therefore,the issues on the reverse channel current and Latch-Up under reverse voltage are dealt with.On the other hand,using the high efficiency bipolar buffering and zero-pole offsetting synchronously in the loop,not only the LDO stability is ensured but also the dropout voltage is minimized.The proposed LDO is fabricated in the BiCMOS process.The testing results show that the reverse voltage can reach 9V,the load and line regulation are 0.25 mV/mA and 0.6mV/V respectively,the dropout voltage on full load（250mA） is only 70 mV.In addition,the quiescent currents at no load and full load are only 7μA and 7.7μA respectively.