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Design >> RF Design >> SP6T switch
https://designers-guide.org/forum/YaBB.pl?num=1147618230

Message started by smanlius on May 14^th, 2006, 7:50am

Title: SP6T switch
Post by smanlius on May 14^th, 2006, 7:50am

If a SP6T switch has proper harmonics at < 1GHz, but high harmonics at 2.5 GHz, what could be the reason for it? The circuit uses PHEMT devices. Does it mean the PHEMT devices are not capable of performing at 2.5 GHz or the harmonics can be improved with proper circuit design without changing the PHEMT devices?

Title: Re: SP6T switch
Post by nsumniak on May 14^th, 2006, 4:07pm

I don't think its because of the High EMT device. You might have to design filters to get rid of the unwanted high harmonics. As an experiment, you could replace your high EMT device with other circuitry(or device) and check for the presence of this high harmonics.

HTH,

Javvad

Title: Re: SP6T switch
Post by smanlius on May 14^th, 2006, 10:09pm

Does this mean the filter in the circuit right now is capable of filtering the harmonics at <1 GHz but not capable of filtering out harmonics at 2.5 GHz? What kind of filter should be used so it can work at both frquencies?

Title: Re: SP6T switch
Post by javvad on May 19^th, 2006, 10:26pm

I would think so. The type of filter would depend on the application you are driving your circuit for. Nail down your criteria and look for Harmonic Filters. A cheap solution would be to use a passive (band pass) filter at which you want to reduce the harmonic.

Good luck

Javvad Qasimi