NFB value conversions?
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Ledvedder5150
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- Location: NJ
NFB value conversions?
Is there a formula for calculating NFB? For example, if a circuit shows 220k off of the 16 ohm tap, what resistance would equal that off of the 8 ohm tap?
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martin manning
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Re: NFB value conversions?
The voltage change at the output goes with the square root of the impedance, and to keep the voltage at the output of the feedback divider approximately the same, the series resistance should be changed in proportion to the source voltage, as in Rnew = Rold*(Zold/Znew)^0.5. In your example, Rnew = 220k*(8/16)^0.5 = 156k.