A TRANSCEIVER DESIGN FOR IMPLANTABLE MEDICAL DEVICES

Abstract

This thesis proposes a transceiver design of an implantable medical device that utilizes inductive coupling coils for power and data transmission. A Class E power amplifier was employed to amplify and transfer power from the transceiver side (external device) to the internal implant. And a novel Load Shift Keying (LSK) demodulator was designed to demodulate the biology data signals transmitted back by the internal implant. The internal implant signals were simulated by an FPGA device. It can work under a variety of modulation indexes and different coding/decoding protocols. It is also able to reduce the whole microelectronic system in both power consumption and device size. The circuits were fabricated in a 180nm CMOS process and a prototype was designed to demonstrate the performance of the proposed demodulator. Measurement results indicated that the circuit can support the power carrier signal of different frequencies and data rates. The core area of the chip is 750?m x 800?m and the achievable minimum modulation index is 5%, whereas the supported data rate is 1 Mbps. With a 1.65V power supply the total current consumption is 3.6 mA.