An 82.9%-Efficiency Triple-Output Battery Management Unit for Implantable Neuron Stimulator in 180-nm Standard CMOS

This brief presents a high-efficiency battery management unit combining a single-inductor dual-output (SIDO) buck converter with two charge pumps (CPs) to provide three voltage levels (6 V, −6 V, and 2 V) for neuron stimulators in implantable medical devices. The stacked power stage in the buck converter mitigates the voltage stress issue in the power stage to manage 3.2–4.8 V battery voltage. By cascading a buck converter and CPs, the voltage across the CP power stage is reduced to generate 6 V and −6 V high voltage outputs without using high voltage devices. As a result, the proposed battery management could provide 6 V, −6 V, and 2 V output voltages from 3.2 to 4.8 V input voltage using a 180-nm standard CMOS process. The measurement results demonstrate that the proposed battery management achieved a peak efficiency of 82.9% with an available input voltage of 3.2–4.8 V.