A millimeter-wave low-loss and high-power switch MMIC using multiple FET resonators

A millimeter-wave low-loss and high-power terminated switch MMIC is developed. Our invented switch is designed based on a non-linear relationship between the parallel resistance of an FET and its gate width. Our measurements of the parallel resistance with different gate width have revealed that the resistance is inverse proportion to a square of the gate width. By using this relationship, we have found the fact that the multiple FET resonators with smaller gate width and high inductance element realize high-Q performance for the same resonant frequency. Since the power handling capability is determined by the total gate width, our switch circuit could reduce its insertion loss, keeping the high-power performance. To verify this methodology, we fabricated a switch MMIC. The MMIC had insertion loss of 2.86dB, isolation of 37dB at less than 33dBm of the input-power.