Electronics Handbook/Circuits/Current Divider

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Current Divider[edit | edit source]

If two elements are in parallel, the voltage across them must be the same, but the current divides according to the resistances. A simple circuit with two (or more) resistors in parallel with a source is called a current divider.


Figure B: Parallel Resistors.

Mathmatic Formula[edit | edit source]

If a voltage V appears across the resistors in Figure B with only and for the moment then the current flowing in the circuit, before the division, i is according to Ohms Law.

Using the equivalent resistance for a parallel combination of resistors is


The current through according to Ohms Law is


Dividing equation (2) by (1)


In general with n Resistors the current is

Or possibly more simply