A feedback controlled coil driver for transcutaneous power transmission

A fully integrated feedback controlled coil driver for transcutaneous power transmission was proposed to power biomedical implants. For a normal power transmission operation, the voltage across the switch that energizes the coil is sampled and compared with ground, followed by an integration to obtain an optimal on-time for the switch such that the coil current was maximized for a given DC input power. The coil driver also provides ASK modulation on the coil current by changing the size of the switch according to the input data. In the normal power transmission operation, a peak-to-peak coil current of ~730mA was obtained with a power dissipation of 71.6mW at 5V.