Design of a Fully Integrated Hysteretic Controlled Reconfigurable Transmitter for Bioimplants

A fully integrated primary equalizer-assisted constant off-time and hysteretic control reconfigurable transmitter at 13.56 MHz for wireless power transfer (WPT) applications is presented. The transmitter can automatically reconfigure to half or full-bridge modes by sensing the operating conditions of the secondary side. Measurement results show instant load transient response, and increased E2E efficiency, and 10% reduced secondary chip area are achieved at the cost of reduced operating distance range w.r.t. fully integrated closed-loop control. The proposed design is implemented with 0.18 μm CMOS process.