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From: erich@inmet.inmet.com
Newsgroups: sci.electronics
Subject: Switched Filters
Message-ID: <17100009@inmet>
Date: 19 Nov 90 17:03:00 GMT
Lines: 32
Nf-ID: #N:inmet:17100009:000:803
Nf-From: inmet.inmet.com!erich    Nov 19 12:03:00 1990



Given some input signal which passes through a high speed switch
and then through a low pass filter.

  in ______./ .______/\/\/\_______ out
          switch     res     |
			    | |cap
			    | |
			     |  
			   ____
			   /// 

If	the switch is turned on and off by some control line at a constant
	frequency Fsw.

	and Fsw >> Fin (input frequency)

	and F-3db of Low Pass Filter > Fin

Will  	Output Signal = Input signal x Duty cycle of control line 
	with no distortion of the output signal relative to the input
	except for attenuation?

Any comments on this type of system would be helpful.
I would simulate it on Pspice but no longer have a copy.

Thanks much...

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