Abstract
The implant device is created with the developing of the technology, and it causes the large change to medical science. With the evolution of the semi-conductor process, the size and power consumption of total device are reduced, making the implant device is more complex in design. Now implant device is combined with wireless power and data transmission, and it not only improves the problem of power supplying but also becomes more convenient in using. This thesis presents an AC-DC converter. This circuit is combined with the rectifier and the controller of the DC-DC converter, so it can get the function of rectification and regulation at the same time, and reduce the area and power consumption of the total device. This circuit also transfers the loading condition back to the external device by LSK (Load shift keying). We can use the feedback signal to determine if the input power is not enough or excessive, which increases the efficiency of the total system. The circuit is fabricated with the TSMC 90nm 1P9M process. The circuit area is 0.071mm2. The circuit can produce a 1V DC voltage with maximum output current of 10mA from an AC input ranging from 1.5V to 2V, at 1MHz to 10MHz. A wireless power and data transmission for biomedical implant SoC is presented in the thesis. The chip contains the presented AC-DC converter. The transmission system utilizes coils inductive coupling the external power into chip, and the AC-DC converter outputs stable voltage for implant circuit. It also transfers the loading condition back to the external device by LSK. After demodulating, the feedback signal can be used to control the output power of external device, which makes the implant device receives the suitable power.