A Hybrid-Resonance Single-Stage Dual-Output Rectifier With High Voltage Difference for Wireless Power Transfer System

Wireless power transfer systems have been widely used in implantable medical devices (IMDs). In these systems, multiple supplies are required to power different modules. Generally, a high voltage is used for electrical stimulation, and a low voltage is used for power-hungry circuits including digital signal processor (DSP), telemetry, etc. In prior works, dual-output rectifiers have been well-established to meet the requirement for IMDs, and there are several typical structures. For example, a dual-output rectifier achieves two outputs by adding DC-DC converters in series with the rectifier. However, this structure occupies a large area and the cascade structure greatly reduces the receiver efficiency. Therefore, single-stage dual-output rectifiers (SSDORs) have been widely studied to reduce size and increase efficiency. In [1], a parallel-resonance full-bridge rectifier is proposed to generate dual outputs, but power transistors up to 6 are required. In [2], a series-resonance half-bridge rectifier with 4 transistors is proposed to achieve dual outputs. However, the existing methods are not capable of obtaining two voltages with a large voltage difference. Series-resonance is more appropriate to transfer high power and parallel-resonance is easier to generate a high output voltage [2]. Therefore, a hybrid-resonance rectifier is very suitable for IMDs.