On Using nMOS-pMOS-Type Cells in a Threshold-Voltage Compensated CMOS RF-DC Rectifier

In this brief, we discuss the merits of using nMOS-pMOS (NP)-type cells instead of nMOS-nMOS (NN)- or pMOS-pMOS (PP)-type cells in a single-ended, threshold-voltage compensated CMOS RF-dc rectifier. By adopting the NP-type cells, we can avoid the degradation of the generated output dc voltage due to parasitic long interconnection wire capacitance, deep N-well to P-substrate junction capacitance, and additional body effect. For comparison, we have implemented two RF-dc rectifiers in a 28-nm 1P11M CMOS process. The measured results show that the implemented RF-dc rectifier with the NP-type cells achieves 0.7-dB higher input power sensitivity and 3x faster recharging time than the other rectifier with the NN-type cells.