The question about deliver VCO outputs to Mixer

[bageduke]

In receiver layout, since mixer is far away from vco for isolation reason. Is there anyway to deliver vco outputs to mixer through LO buffers efficiently? I know that current mode signals maybe the best for long wire, but it still encounter the large mount of power lose.

Is there anyway better than current. Or some better layout technique?

Thanks,

 

[khouly]

i think u need a good VCO buffer , before the Mixer , so u can hold ur power to the mixer

khouly

 

[bageduke]

Yes, so far I am using current mode buffer to deliver power to mixer, but since it's long wire and high speed(around 6GHz), I need a few milli amps to deliver the signals.

Do you have any example about VCO buffers which is efficient?

Thanks a lot.

 

[BigBoss]

Emitter followers are used to deliver milliamper rated high frequency currents..

An example..
In my recent project, I have designed a emitter follower that has capable to deliver 6.8mA onto 42-j18 Ohm impedance.

It has worked quite good with approx. 17um by 10um bipolar.

 

[bageduke]

Now I only have CMOS device available to use and I would like to know if fewer current could do the job and how.

 

[khouly]

u can use source follower , with good current capablity , will work

khouly