On-Chip RMS Detector using CMOS Quad for RF Testing

An RMS detector using CMOS Quad for the on-chip RF testing is introduced. When a differential voltage is applied across a CMOS quad, it generates both even and odd output currents. Even component of the generated current is isolated and converted back to voltage using inverse function. Higher frequency components of the output voltage is filtered out. The DC or low frequency output of the detector is proportional to the RMS value of the input signal. The detector offers a high input impedance and small area overhead, and thus can be used for on-chip built-in testing of critical blocks of the transceivers or other RF blocks. The design is carried out in 0.18 mum TSMC process.