A Sub-Micron CMOS Programmable Charge Pump for Implantable Pacemaker

In pacemaker design the mainconcerns are reliability, functionality,operating life and miniaturization. Afundamental role in miniaturization is dueto the increased circuit integration; hencelow power circuit solutions that can beintegrated in sub-micron CMOS technology arehighly desirable. This work proposes avoltage multiplier suitable for pulse outputgeneration in an implantable pacemaker,implemented in a standard, low-cost CMOS 0.8 m technology. The circuit can operatewithin a supply voltage range of 2.8 V to 2V, corresponding to the voltage capabilityprovided by the single lithium iodine cell,ubiquitously used in pacemaker. Fineprogrammability of the output has beenachieved, thus allowing the choice of theoptimum tradeoff between stimulationefficacy and battery longevity. Moreover theproposed solution takes care of minimizingthe parasitic coupling and disturbancesbetween the charge pump and other blocks inthe system. Finally the measured steady statecurrent consumption is smaller than .