关键词: T型开关, 高隔离度, 带宽, 串扰

Abstract: In order to solve the low isolation of traditional CMOS switches at high frequency, a low crosstalk, wideband and high isolation level video switch circuit is proposed for video signal transmission system. The proposed switch is composed of two complementary T-type PMOS and NMOS switches, which achieves a 4 MHz turn off isolation of -70 dB and a high bandwidth. Using 0.5 μm P substrate N-well CMOS technology, the spectrum simulation results show that the input signal in the range of -2~2 V, the switch's -3 dB is greater than 50 MHz, the switch time is less than 50 ns, and the dynamic characteristics are good.

Key words: T switch, high isolation level, bandwidth, crosstalk