A Dual-Mode One-stage R³ Rectifier with Wide Loading Range for Implantable Medical Devices

A 13.56 MHz wireless power receiver with a reconfigurable resonant regulating (R<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>) rectifier for implantable medical devices is presented. The receiver adopts the 0X/1X dual-mode modulation and achieves voltage rectification and regulation in one stage. The PWM controller consists of a ramp generator and a Type-II compensator. Hybrid on/off-delay compensation with analog V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dd</inf>-sensing and digital multiple pulsing blocking reduces the delay of the active-diode path. Embedded level-shift drivers adaptively provide high voltage to turn off the high-side PMOS active diodes with the mode signal, and they can be decoupled from driving the power PMOS transistors, thus enhancing the overall efficiency. Measurement results show steady delivery of 5V at a load of 400Ω and stable load transients between 1mA to 20mA. The measured maximum power conversion efficiency (PCE) is 92% for a load resistance of 167Ω and the load resistance can be as large as 10kΩ.