ExpEYES

The schematic is wired as shown in the diagram below. The voltage across the diode is measured on A1. The anode of the diode is connected to PV1, through a 1k resistor. Voltage at PV1 is incremented in steps and at each point the voltage across the diode is measured. The current is calculated from i = (PV1-A1)/R. The diode used is 1N4148, silicon diode. The experimental setup and the screenshot are shown below. The results shown are for 1N4148 silicon diode, red and green LEDs.

Python Code

A Python code may be written to plot the IV graph. The applied voltage is incremented in steps and voltage across he diode is measured. The current is (Vapplied - Vdiode)/Resistance. Python program

import eyes17.eyes
p = eyes17.eyes.open()

R = 1  # in kOhms, gives current in mA
x = []
y = []

v = 0.1
while v < 5:
	p.set_pv1(v)
	vd = p.get_voltage('A1')
	i = (v-vd)/R
	x.append(vd)
	y.append(i)
	print (vd, i)
	v += 0.1

import matplotlib.pyplot as plt
plt.plot(x,y, 'x')
plt.show()