[NLRS] PA3GIE 10GHz high power SSPA

[tosca005 at umn.edu]

On Oct 19 2012, Dr. Gerald N. Johnson wrote:

>
>
>I read a couple weeks ago that the DB6NT 50 watt amp is $3500.
>
>There are some bare chips from Triquint that will do 90 watts for only 
>$240 each in small quantities. Trouble is they need wire bonding after 
>soldering to the heat sink with Sn/Au alloy solder. I think there's a 
>presentation this weekend at MUD that's not in the printed proceedings. 
>Maybe it will be in the CD if there is a CD. Set for 3:30 Saturday:
>"3:30 50W 10GHz SSPA using GaN, WA6KBL" from the presentation schedule. 
>I wish I could see that presentation or read it. I have my own ideas 
>thinking a Sn/Bi low temperature solder would be far easier to find and 
>to use and that rather than multiple ball bonds one might solder down PC 
>board traces right close to the bare chip and make the chip connections 
>with silver bearing epoxy and thin copper foil. Then cover the assembly 
>with a good curing board coating though that might increase the 
>dielectric constant and be a poor quality dielectric at the same time. 
>Just to project the chip from the atmosphere. There is a 10 watt version 
>of the Triquint chip far less expensive that is like 1/8 th of the 90 
>watt chip. In fact the S parameters on the high power chip are for the 
>10 watt chip, repeated 8 or 9 times for the 90 watt part.
>
>73, Jerry, K0CQ

Hmmm...

Maybe NB0M can offer some insight into the assembly issues. He has 
experience with wirebonding (and I believe he owns the equipment to do it). 
Ed???

73 de W0JT