Current Divider


This current divider produces an output current, Io, that is proportional to the input current, Is. The output current is measured using a ammeter. The input current is the current of the current source. The constant of proportionality is called the gain of the current divider. The value of the gain of the current divider is determined by the resistances, R1 and R2, of the two resistors that comprise the current divider.


The values of the input, Is, and of the resistances, R1 and R2, can be adjusted using the scroll bars.



Challenges:

  1. Set R1 = 20 and R2 = 40. Predict the value of Is required to cause Io = 2.0. Use the scrollbars to check your prediction.

  2. Set R1 = 20 and R2 = 40. Determine the range of output current that can be obtained by adjusting the input current.

  3. Set R1 = 20 and Is = 10. Predict the value of R2 required to cause Io = 7.5. Use the scrollbars to check your prediction.

  4. Set R1 = 20 and Is = 10. Determine the range of output current that can be obtained by adjusting the resistance R2.

  5. Set Is = 8. Adjust R1 and R2 so that Io = 2.

  6. Adjust R1 and R2 so that R2 = 4*R1. Measure the value of the gain of the current divider. (If Is=1 then Io = gain * 1 = gain. That is, the output current is "numerically equal" to the gain, but has different units.)

  7. Adjust R1 and R2 so that R1 = 4*R2. Measure the value of the gain of the current divider.

  8. Adjust R1 and R2 so that R2 = R1. Measure the value of the gain of the current divider.

  9. Adjust R1 and R2 so that the value of the gain of the current divider is 0.9.

  10. Determine the largest value of gain that can be obtained when R2 > R1.