current gain for differential amplifier is generally not derived.why?

Question

jismondev

Answer 1

Differential amplifiers usually have very high input impedances so it becomes difficult to force current through the input without a very high 'head' voltage. That 'head' voltage is usually higher than the common mode voltage of the amplifier, making current gain a moot point.

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Answer 2

If your looking for a number like a 20 db gain or something then your going to be let down.. There should be though a current gain on the specs of the diff-amp . What it does is look at the biased input then by amplifying (numerically-this is your number ) it has its out put . The differential part is that its gain is dependent on input and on a lot of IC units this is not linear at all...Wish i could help more but application is everything here...Op amps and Even old transistor type 2n222 are when Scr'd are a type of diff-amp...Because at lower than gate voltage the amp turns off...so its differential at 0 and at 1 ...Good luck with this one ...try wikipedia or just google diff amp and get makers specs on your piece of equipment....From the E......

Answer 3

most op amps dont change the current it is the voltage that is amplified. all op amps have a very high impedance on the input terminals and a very low impedance on the output terminals. Unless you use a op amp in current amplyfing set up.

so the current will depend upon the voltage at the output and the load resistance.