200nA low quiescent current deep-standby mode in 28nm DC-DC buck converter for active implantable medical devices

The proposed deep-standby mode (DSM) is used in 28nm power management unit (PMU) for long-term usage in active implantable medical devices (AIMD). The PMU can upgrade its normal mode with the proposed embedded auto-cancellation (EAC) technique in order to have high accuracy even if the battery is aging and the PVT variations occur. The test chip fabricated in 28nm CMOS process features low quiescent current of 200nA and output voltage accuracy of 98%. Seamless transition among the DSM and the accurate mode demonstrates both low quiescent current and high accuracy can be achieved in the proposed PMU.