The I-V curve and the C-V curve of the PIN diode.
The SPST switch circuit chip is depicted in Figure 2 (a), which is designed using the principle of a parallel switch between PIN diodes and microstrip transmission lines. To improve isolation, three GaAs PIN diodes are chosen to be impedance matched in cascade to achieve the best performance index. The bypass with PIN diode and sector low-pass filter are matched on the high-impedance line of the SPST switch to reduce the insertion loss of the device. The PIN diode can loop in the circuit by bonding to the ground at the opposite end of the high-impedance line. The on state of the switch corresponds to the reverse state of the PIN diode, and the off state of the switch corresponds to the forward state of the PIN diode.