Post subject: Inductance lead effects Posted: Fri
Sep 09, 2005 3:59 am
Mar 15, 2005 11:43 pm
currently designing 3.5GHz power amplifier module, with the clip
pin lead. I'm wondering whether the inductance of the lead (especially
output lead) will significantly affect the performance?
also due to the substrate thickness, the lead will be bent to connect
to evaluation board (jig). So, there'll be gaps in between. I'm
not sure whether it'll affect the performance especially at 3.5GHz
I've done some simulation by adding some inductance
at the output. The gain is not significantly affected, but there's
some effect at output return loss ( although not "high" ). Since
so far, I only be able to do small signal simulation, I'm worried
that it'll affect power performance at the end.
kindly advise me how to do the "right and accurate" simulations
to observe/ predict the effects on overall performance?
to prepare some anaylsis before send to fabrication.
advice is much appreciated.
Thanks and Regards,.
Post subject: Posted: Fri Sep 09, 2005
Joined: Mon Jun 27, 2005 2:02
understand compleltly from your description what is a clip pin lead
Could you tell what is the package type?
mean that there is an air gap between one pin of yor active device
to the substrate this will certainly cause a discontinuity in the
impedance and will affect your return loss. If this occurs at the
output it could be worse, because as you may know, the output is
much more dominant in PA design.
I think that you can simulate
an air-gap by measuring the dimensions of the air-gap and add a
shape(s) of transmission line(s) with the same dimensions that has
a dielectric coefficient of Er=1 (Dielectric coefficient of air).
Please provide the information above so I can help you more.