# Lab 8 TF EIM

Lab 8 The Diode Objective: Measure the current-voltage curve of a silicon diode.

# Reverse current

1.) Construct the circuit below using a DC power supply, a diode.

2.) attach an Oscilloscope set to 1M input impedence so the probe is located at point B. The oscilloscope's internal resistance will serve as a Resistor (R) to measure the voltage across the diode and calculate the current.

3.) Measure the diode reverse current as a function of the DC supply voltage. (30 pnts)

4.) Fill in the blank. The reverse biased diode act as a constant _______________ source. (5 pnts)

# Forward Current

1. now swap the diode direction and repeat the measurement in the previous section.

# Graph

1. make the same measurements in parts 1 and 2 above for a germanium diode.
2. Plot the diode current (on the ordinate) versus the diode voltage (on the abscissa)for both diodes on the same graph. (50 pnts)

# Questions

1. The reverse biased diode acts like a constant ____________. (10 pnts)
2. The forward biased diode has a very __________ resistance. A reverse biased diode has a very ____________ resistance.(10 pnts)
3. The approximate DC forward resistance for diode #___________ is _________ when the forward current is _______________.(10 pnts)
4. The approximate DC reverse resistance for diode #___________ is _________ when the forward current is _______________.(10 pnts)
5. The silicon diode #___________ has an approximate turn on voltage of ___________.(10 pnts)