# Current Source

1. May 18, 2014

### Duave

1. The problem statement, all variables and given/known data

Question 1: For the circuit below, determine what happens at maximum resistance when varying the 10K (decade box) variable load.

Question 2:Explain the answer to the previous question, in terms of voltage compliance of the current source.

Question 3:What causes detectable variations in output current as the load is varied within the compliance range.

Question 4:Verify the explanation in the previous question, by making use of diagrams.

https://scontent-a.xx.fbcdn.net/hphotos-frc3/t1.0-9/10169340_10152051867080919_2806929430313118200_n.jpg

2. Relevant equations

No equations

3. The attempt at a solution

Solution 1:
At maximum resistance, the saturation is reached, and the diode does not work properly anymore, as the collector current begins to drop.

Solution 2:
At maximum resistance, the collector current and the emitter voltage will change from being 1mA, and 1 V, respectively.

Solution 3:
The detectable variations in output current are the due to the the ammeter's installation into the circuit.

Solution 4:

In the diagram below, the top figure is actual data collected from experiment, and the lower image is a theoretical model of how transistors function. The similarities can be seen.

https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-prn2/t1.0-9/10301071_10152051925355919_7760044223328917828_n.jpg

Are all four of my answers correct?

2. May 19, 2014

### Staff: Mentor

Diode?

Where did these values come from?

Are you given an approximate value for β?

Last edited: May 19, 2014