RF POWER TRANSISTOR
Dear friend,
Looks like, due to the high VCC you need, that the best option is to use a LDMOS in your application.
You may want to have a look on http://www.cree.com/Products/rf_selectorguide.asp where you will find lots of devices in the frequency and power range you are looking forward.
NandoPG
Thanks!
I want to use broadband rf trnsistor (such as mrf284).I don't konw the LDMOS ( UGF18060) which can use from 1GHz to 2GHz.THE UGF18060 is internally matched from 1.8GHz to 1.85GHz.
In site of Motorola or Philips you can find LDMOS for broadcasting and base station. Some of them are not prematched and you can use them. They works very well and never fail
regards
ste
Dear friend,
I am sorry, I had not undertood you want to design an amplifier with one octave bandwidht. Being so, I don't think you are going to succeed in a 1 octave amplifier design with unmatched high power LDMOS.
This is why the Q for the input and output impedances for high power devices by itself is around 4 to 5 what makes the design very hard to be implemented and that is also why some manufacturers prematch their LDMS, paying a constrained bandwidth.
Sorry for my misunderstanding,
NandoPG
To say about an RF power transistor that never fail you have to have a lot of courage :)
You might also want to look at Cree Semicondutor.
Their LDMOS FET's are a little better than Motrola's.
At least the 90&30 Watt'ers.
\/\/ww.cree.co/\/\
Cheers
Hello,
I'm designing a PA from 1 to 2 GHz by using a pair of MRF284 in Balanced configuration. This comes from a former design which didn't delived strong power. I have a 4.5 W average of input power and, currently, the power delivered at the output
is about 27 W average. The small signal gain si 8.5 dB (+/- 1,5 dB) and aach transistor is biased for class a operation mode (1 A IDQ).
In the file attached is displayed a single section of the PA.
I wonder if is possible to get better performance from this PA;
I have ADS and Ansoft Designer as simulator.
Thanks
Andrea
I think LDMOS transistors from freescale come as a module (Class-AB, common-source configuration), can someone confirm this?
