Passive Amplification of Supply Voltage in an Implantable Chip

Abstract:
Power pads of implantable devices should be driven with AC voltages having low amplitudes as well as high frequencies to support long lifetime for the device. In our previous publication [1], internal supply voltages in the range of 2V ? 2.4V are required. To apply an input AC power voltage with an amplitude lower than diode’s on-state voltage drop, a passive amplification circuit is advantageous. This circuit raises the amplitude of the input voltage and makes the application of a rectifier or charge pump in the following stage possible. In this paper, a method for this first step is presented using a series onchip resonance circuit. In the resonance circuit design, the main concern is the development of an integrated planar spiral inductor. This inductor is designed by using fundamental equations from literature and investigated by doing Maxwell RF simulations in Sonnet software. Index Terms —Passive Amplification, Parameter Extraction, Inductor, Resonant Circuit Amplification