CMOS for Class E Amp - RF Cafe Forums

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RF
Post subject: CMOS for Class E Amp..
Unread postPosted: Thu Apr 22, 2004 3:15 pm

I am looking for any information of the CMOS which can be used for Class E Amp.
If you have anything for it, plz reply.

[/b]

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Kirt Blattenberger
Post subject: Google to the rescue
Unread postPosted: Thu Apr 22, 2004 10:48 pm
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Joined: Sun Aug 03, 2003 2:02 pm
Posts: 308
Location: Erie, PA
Greetings:

Here's a good place to start if you don't have much to go on yet.

http://www.google.com/search?hl=en&ie=U ... +amplifier

If you can't find what you want there, you might try providing information more specific to your application.

Good luck.

- Kirt B. :mrgreen:

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RF
Post subject: Re: Google to the rescue
Unread postPosted: Fri Apr 23, 2004 9:16 am

Thank you for your reply.
I've got some papers there. I am the beginner for it, so I am still hang around..
If I need moe after studyng, I will post again.

Thank you.

From Bo

Here's a good place to start if you don't have much to go on yet.

http://www.google.com/search?hl=en&ie=U ... +amplifier

If you can't find what you want there, you might try providing information more specific to your application.

Good luck.

- Kirt B. :mrgreen:[/quote]

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Puck
Post subject: class e amplifier for 1800MHz
Unread postPosted: Wed Apr 28, 2004 3:41 pm

For RF, cell phone application it is no no. Just buzzword. There are some academic articles running the amplifier in switched power supply. There are never mentioned real-life measurements. :lol:

What it means - FM modulation of FSK (GSM) needs AB class amplifier operation, or little bit linearity to mathc the FCC/ETSI spectral mask. The overall efficiency is already set by the AB class bias.

Linear modulation - direct E class operation is BS. The device could be run in switched mode, processing only the phase information on input. Works like NAND gate. Vcc is modulated by the signal amplitude envelop. Overall result - expenses for filtering and additional circuits will kill overall advantage in efficiency. And FCC will seize it.

Audio - could be done as PWM pulse width modulation. Filtering the output with cap, you get the RMS of pulsed signal. Caveat - you can not run any RF sensitive device, receiver etc. in the vicinity of this broadband spectrum generator. FCC/ETSI will hunt you as a vermin for poisoning shared public frequency spectrum.

Opinion - the reused idea of switched power supply with high effieciency is only switched power supply. It is not power amplifier. Academics use the buzzwords "class e amplifier" to attract financing.

D. Tomanek

Posted 11/12/2012