Digitally timed CMOS rectifier for wireless power transfer

A voltage rectification circuit for a medical device having an internal coil and internal circuitry, the voltage rectification circuit comprising:

• a rectifier having actively driven low-side first type transistors and cross-coupled second type transistors, a first type being one of N-type and P-type and a second type being an opposite one of the N-type and P-type, each low-side first-type transistor being configured with a first type diode;
• the rectifier configured to receive a time varying periodic voltage from the internal coil and to output a rectified received voltage, the actively driven first type transistors being further configured to receive an enable signal to cause the rectifier to switch between rectifier states;
• a comparator configured to detect when the received time varying voltage crosses a voltage threshold, the voltage threshold being sufficiently low to enable each actively driven first type transistor to conduct through the first type diode;
• digital timing circuitry configured to:
• estimate windows of time for which the received time varying voltage can be expected to conduct through the first type diodes;
• and
• generate the enable signal to enable each actively driven first type transistor to conduct through a channel of the actively driven first type transistor while bypassing conduction through the first type diode.