Re: Attenuators - theory and the design of.
Wendy,
(Love those Teledyne relays)
There is something about your attenuator that I don't understand, maybe its for some reason. Looking at your attenuator sections the input and output impedance starts out for the first section at over 200 Ohms then it drops with each section and the output network is around 50 ohms.
I think it should be that each attentuator section ideally would have a 50 Ohm input and output impedance (but I might need correcting on this)
I have in the past worked out the formula for this myself (it has been checked) attached. The only thing though the formula was configured for "attenuation factor" so a x2 attentuator would drop the level to 1/2 or a x10 attenuator would drop it by 1/10. So to use this formula you would convert your dB values into an attenuation factor A. The formula could be simplified, but it works as it is.
If you insert 50 in for the Z in the formula the results will make sure the input and output Z of each attenutor section remains at 50R
|