Switches on all-pass phase shifter
时间:04-06
整理:3721RD
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I'm designing a four bit wide band phase shifter (22.5,45,90,180 deg) which include series switches at input/output of each section combined with all-pass networks. My question here is that I'm not sure if I need to add DC blocking caps at the input/output of each section or do I just leave the D/S of the switch floating? Most of the examples I've seen don't seen to have these caps with each stage directly connected to the other. This is being implemented as a GaAs MMIC chip. When I do add these caps, my insertion loss increases by over 2 dB.
Thanks
Thanks
Those switches needs the DC blocking caps. For example most of the stand alone GaAs switches (packaged) have the DC blocking caps incorporated, and don't need to put external.