S
steve
- Jan 1, 1970
- 0
Hi,
I'm trying to impedance match a 250-450MHz VCO (designed for a 50 Ohm
load) to an AD8343 mixer which has a 2.7+6.8j input impedance.
I'm fairly new to impedance matching in the wild (have only got limited
pure-resistance based impedance matching from university), so I'm
getting a bit stuck here.
I've read a bit about LC matching networks but it seems that they're
only for narrowband applications, unsuitable for my setup. I've also
come across using transformers for wideband matching applications, but
I'm unsure how to apply this. From what I've read, the impedance
relationship of a transformers primary and secondary coils is:
Zs/Zl = (Ns/Nl)^2
So for my application I need a transform with a turns ratio which
satisfies the following:
50/(2.7+6.8j) = 2.52-j6.35 = (Ns/Nl)^2
But this gives me a complex transformer ratio, which doesn't seem
possible.
I'm a little stuck at the moment, can anyone explain to me where I
should go from here?
Steve
I'm trying to impedance match a 250-450MHz VCO (designed for a 50 Ohm
load) to an AD8343 mixer which has a 2.7+6.8j input impedance.
I'm fairly new to impedance matching in the wild (have only got limited
pure-resistance based impedance matching from university), so I'm
getting a bit stuck here.
I've read a bit about LC matching networks but it seems that they're
only for narrowband applications, unsuitable for my setup. I've also
come across using transformers for wideband matching applications, but
I'm unsure how to apply this. From what I've read, the impedance
relationship of a transformers primary and secondary coils is:
Zs/Zl = (Ns/Nl)^2
So for my application I need a transform with a turns ratio which
satisfies the following:
50/(2.7+6.8j) = 2.52-j6.35 = (Ns/Nl)^2
But this gives me a complex transformer ratio, which doesn't seem
possible.
I'm a little stuck at the moment, can anyone explain to me where I
should go from here?
Steve