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Well not exactly, because there is always a mismatch....one diode will take more current than the other or like that.....so you will never get double amperage.
Well I guess our questions are concerned with the basic principles of electric circuitry, connecting parallel resistances means one can get half the resistance of one, and thus the current dissipated is doubled.
The point of doubling the current isn't always true though as it will mainly depend on the circuit. Sometimes the current stays constant and is divided by each diode, i.e. the current through the each diode is half the original current.
Generally, it is not a good idea to parallel discrete diodes, since the on-voltage differences will crreate huge differences in current, so the diodes will never share the current equally, as you would wish.
However, it is generally accepted that diodes on the same die can be paralleled. Thus, dual diodes can be paralleled. In fact, even the manufactures rate them for twice the current of the individual diodes. For example, an MBR6045 is called a 60A diode, although in fact each diode inside is only rated at 30A.
The general solution to current sharing is to put small resistors in series with each diode and put the group in parallel. There should be a few tenths of a volt drop across the resistors at the maximum current. This will produce added losses. This should only be done if you cannot get a single diode that can handle the required current.
This configuration can be used to increase the overal current. and to make the currents of two diodes be equal, you may put two small resistors in series with the diodes. by this, the inverse current remains neglabe. Another solution to this problem is to put a large resistor in parallel to the combination of two diodes. You may reffer to "Micro Electronic Circuits" by Sedra.
hi
all what our friends said above, but be careful since no towdiodes evevn from the same type are identical, and so the current sharing will not be equal , to forxe ot to be equal you should add a positive tenp coeffcient resisto in series with each dide
a second idea is if you want to pass 30 amps from a 15 a diode use 3 or 4 in paralell rather than 2
best regards
when you put two diodes in parallel (which are identical)(forward bias) then it is like putting two resistors in parallel and hence the resistance of the path is gonna go down as half and hence leading to doubling of current
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