To calculate the output current in a current divider, use the formula Ii = Iin * (Rt / Ri), where Ii is the output current and Rt is total resistance.
Calculating the Output Current of a Current Divider
To calculate the output current of a current divider, you must first understand the principles behind its operation. A current divider is an electrical circuit that distributes an input current among multiple parallel paths based on the resistances or impedances of the connected components. The working principle of a current divider is based on Ohm’s Law and Kirchhoff’s Current Law.
Current Divider Formula
For a current divider with two resistors, R1 and R2, the output currents can be calculated using the current divider formula derived from Ohm’s Law and Kirchhoff’s Current Law:
I1 = Iin * (R2 / (R1 + R2))
I2 = Iin * (R1 / (R1 + R2))
Where:
- I1 and I2 are the output currents through R1 and R2, respectively.
- Iin is the input current.
- R1 and R2 are the resistor values.
General Formula for Multiple Resistors
For a current divider with multiple resistors, the general formula for calculating the output current through a resistor Ri is:
Ii = Iin * (RT / Ri)
Where:
- Ii is the output current through resistor Ri.
- Iin is the input current.
- RT is the total resistance of the parallel combination, calculated as the reciprocal of the sum of the reciprocals of the individual resistances.
Example Calculation
Suppose you have a current divider with an input current of 10 A and two resistors, R1 = 5 Ω and R2 = 10 Ω. To calculate the output currents, apply the current divider formula:
I1 = 10 A * (10 Ω / (5 Ω + 10 Ω)) = 6.67 A
I2 = 10 A * (5 Ω / (5 Ω + 10 Ω)) = 3.33 A
Therefore, the output currents through R1 and R2 are 6.67 A and 3.33 A, respectively.
Understanding the current divider formula and applying it correctly will help you analyze and design electronic circuits that employ current dividers.

