A 1.5V 120nW CMOS programmable monolithic reference generator for wireless implantable system.

We implement and characterize a 1.5 V 120 nW CMOS programmable monolithic reference generator for wireless implantable system. The proposed generator is optimized to be tolerable for power supply variation in a small area with programmability to generate various reference voltages and currents. The measured power line sensitivity are 0.02 / 1.1%/V for voltage and current reference, respectively. This reference generator can operate for input voltage ranging from 1.5 V to 3.5 V and implemented in an area of 0.011 mm(2), which is the smallest monolithic reference generator in 0.25 μm technology to the best of our knowledge. The output can vary from 20 nA to 33 nA for current reference and from 0.71 V to 1.03 V for voltage reference.