Broadband Root-Mean-Square Detector in CMOS for On-Chip Measurements of Millimeter-Wave Voltages

A root-mean-square Schottky diode detector for estimating millimeter-wave (80-110 GHz) signal voltage using dc or low-frequency measurements for debugging and self-testing is demonstrated. The detector is realized in a 45-nm CMOS process without any process modifications. The detector gain at 30-mV_rms input voltage is 11 V^-1 . The insertion loss is less than 0.2 dB, and the flatness of the detector gain over 80-110 GHz is 15%. The input dynamic range is greater than 29 dB, and the size of the detector including the filter capacitor is 340 m².