AM Power Amplifier - RF Cafe Forums

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SDO
Post subject: AM Power Amplifier Posted: Tue Sep 22, 2009 2:50 am

Captain


Joined: Tue Aug 26, 2008 5:18 am
Posts: 22
Location: UK
Hello all,
I need some help about designig power amplifier for 150kHz-1650kHz appliaction.
Gain requirement is better than 40dB with P1dB above 43dBm. Supply voltage 24V.
It is going to be two stage single ended design. I was thinking about using MW6004N as a driver. I am not sure if MRF281 can be used for this application as well.
Any info about the available devices along with some literature for matching networks will be appreciated.

Regards.


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LM317
Post subject: Re: AM Power AmplifierPosted: Sat Sep 26, 2009 9:53 pm

Captain

Joined: Tue May 20, 2008 8:13 pm
Posts: 5
Looks like the MRF281 is going to be out of production soon, so I wouldn't recommend designing it into a new product. It's advertised for applications with frequencies from 1 to 2.5 GHz, way far away from the AM band. Its s-params only go down to 100 MHz.

http://www.freescale.com/files/rf_if/doc/data_sheet/MRF281.pdf

I can't find any data on an MW6004N. Who makes it?


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SDO
Post subject: Re: AM Power AmplifierPosted: Mon Sep 28, 2009 9:34 am

Captain


Joined: Tue Aug 26, 2008 5:18 am
Posts: 22
Location: UK
Hi,
Thanks for your response. Yes, you're right not to use MRF281. The other device was MW6S004NT1
http://www.freescale.com/webapp/sps/sit ... T1&fsrch=1
Any idea about power device which can deliver 10-20w at 1MHz and 24-28V?
Thanks


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IR
Post subject: Re: AM Power AmplifierPosted: Tue Sep 29, 2009 3:15 pm

Site Admin


Joined: Mon Jun 27, 2005 2:02 pm
Posts: 373
Location: Germany
You may try Polyfet www.polyfet.com

They have line of RF Power Transistors for low frequencies also suitable for AM.

Good luck!

_________________
Best regards,

- IR


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SDO
Post subject: Re: AM Power AmplifierPosted: Wed Sep 30, 2009 3:48 am

Captain


Joined: Tue Aug 26, 2008 5:18 am
Posts: 22
Location: UK
Hi,
Thanks for your reply. Polyfet has got some devices and I have seen some more at semelab as well.
Thanks gain.









Posted  11/12/2012