Hi,
I was thinking that two couple conductors (a capacitor) is similar to two coupled inductors (a transformer), but the difference is that a capacitor usually has a plate area ratio of 1:1.
So if a capacitor in an AC coupled configuration is constructed with a plate area ratio of 2:1 for the "primary" to "secondary" conductors, will this transform an input signals voltage in a 2:1 ratio on the secondary conductor?
cheers, Jamie
Wrong! The capacitance is determined by insulation characteristics, distance between plates AND _common_ area of both plates. In your example you would have a capacitor determined by the smaller plate (+/- edge effects).
Have fun
Stanislaw Slack user from Ulladulla.
The short answer is "No". A capacitor and a transformer operate according to two different laws of physics. The transformer operates according to Lenz's law where v = N(dphi/dt), i.e., the voltage coupled to the secondary is equal to the number of turns times the rate of change of magnetic flux with respect to time. The capacitor operates in accordance with i = C dv/dt, i.e., the current through a capactitor is equal to the capacitance times the rate of change of voltage with respect to time. The capcitance of a capacitor is roughly proportional to the overlapping area of the two plates. I say "roughly", because there are some fringing effects near the edges of the plates, where the electric field is not perpendicular to the plates, but "fringes" around the edges. I hope this helps. regards, Jon
I dont realy see any similarity between a capacitor and transformer, for a start a capacitor is a 2 terminal device so the voltage is usualy referenced to the other plate, therefore there is no 'output voltage' as such.
unrelated, ... if you charge the capacitor up and move the plates further apart you get a voltage increase.
Colin =^.^=
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