Capacitive coupled full-wave rectifier for rectangular power signals

In this paper, a fully integrated bridge rectifier is presented. It is specialized for fully differential rectangular power supply waveforms. The rectifier is implemented in AMS 0.18 μm 6M/1P high voltage CMOS process with metal insulator metal (MIM) capacitors. Combining self driven switches with capacitive coupled switching gates the proposed rectifier shows very little output ripple without the need for a big output capacitance (C_out). By introducing coupling capacitors (C_C), switching time is significantly reduced and the losses during polarity change can almost be eliminated. Simulation results show that the output voltage ripple (AV_out) becomes mostly a function of the load current. The output capacitance can be reduced at least by a factor of 2 and still achieve the same output ripple as compared to non-capacitive coupled architectures.