ExpEYES/C3/Diode-Rectifier-Transistor/English-timed
| Time | Narration |
| 00:01 | Hello everyone. Welcome to this tutorial on Diode, Rectifier and Transistor. |
| 00:08 | In this tutorial, we will study:
Working of PN Junction diode Diode as rectifier Diode IV characteristics Light emitting diode (LED) IV characteristics Out of Phase inverting amplifier and Transistor CE. |
| 00:26 | Here, I am using:
ExpEYES version 3.1.0 Ubuntu Linux OS version 14.04. |
| 00:36 | To follow this tutorial, you should be familiar with ExpEYES Junior interface.
If not, for relevant tutorials, please visit our website. |
| 00:47 | Let's first define a PN junction diode. |
| 00:51 | PN junction diode:
is a semiconductor device which allows current to pass through in one direction. It converts alternating current to direct current. |
| 01:03 | We will demonstrate working of PN junction diode as a half wave rectifier. |
| 01:09 | In this experiment, we will:
Convert AC signal into a DC signal in forward bias Convert AC signal into a DC signal in reverse bias Filter the AC component using a capacitor. |
| 01:25 | Now, I will explain the circuit connections.
1K resistor is connected between GND and A2. PN junction diode is connected between A2 and SINE. SINE is connected to A1. Here SINE is an AC source. This is the circuit diagram. |
| 01:46 | Let's see the result on the Plot window. |
| 01:49 | On the Plot window, click on A1 and drag to CH1. A1 is assigned to CH1. |
| 01:56 | Click on A2 and drag to CH2. A2 is assigned to CH2. |
| 02:01 | Move the mSec/div slider to adjust the waves. Two sine waves are generated. |
| 02:10 | Black trace is the original sine wave. |
| 02:13 | Red trace is the rectified sine wave. Negative half of the red trace is completely removed, as it is a rectified wave. |
| 02:23 | Positive half starts after diode attains a threshold voltage. AC signal gets converted into a DC signal, in the forward bias. |
| 02:34 | Click on CH1 and drag to FIT.
Click on CH2 and drag to FIT. |
| 02:40 | Observe the voltage and frequency values on the right side of the window. |
| 02:45 | On reversing the diode connection, AC signal gets converted into a DC signal in the reverse bias. |
| 02:52 | We will filter the sine wave using a 10uF (micro farad) capacitor. In the same connection, replace 1K resistor with a 10uF (micro farad) capacitor. |
| 03:04 | This is the circuit diagram. |
| 03:06 | Let's see the result on the Plot window. |
| 03:09 | On the Plot window, we can see that rectified sine wave is filtered. Here, AC component is called ripple in the DC. |
| 03:20 | Now we will demonstrate diode IV characteristics of PN junction diode and LEDs. |
| 03:27 | I will explain the circuit connections. PVS is connected to IN1 through 1K resistor. |
| 03:34 | IN1 is connected to GND through PN junction diode. |
| 03:39 | This is the circuit diagram. |
| 03:41 | Let's see the result on the Plot window. |
| 03:44 | On the Plot window, click on EXPERIMENTS button. Select Diode IV. |
| 03:51 | EYES:IV characteristics and Schematic windows open. Schematic window shows the circuit diagram. |
| 04:00 | On EYES:IV characteristics window, click on START button. |
| 04:05 | Current initially remains constant but rises as voltage increases to 0.6 volts. |
| 04:13 | Click on FIT button. |
| 04:16 | Diode equation and Ideality factor are displayed. Diode's ideality factor varies between 1 and 2. |
| 04:26 | We will replace diode with red, green and white LEDs, one by one, in the circuit. |
| 04:33 | Please note LED glows in only one direction. If it does not glow, turn to opposite direction and connect again. |
| 04:43 | Let's first connect red LED in the circuit. This is the circuit diagram. |
| 04:49 | On the Plot window, click on EXPERIMENTS button. Select Diode IV. |
| 04:56 | On EYES:IV characteristics window, click on START button.
In the diode IV curve, current initially remains constant but rises as voltage increases to 1.7 volts. |
| 05:11 | Let's connect green LED in the circuit. |
| 05:15 | On the Plot window, click on EXPERIMENTS button. Select Diode IV. |
| 05:22 | On EYES:IV characteristics window, click on START button. |
| 05:27 | In the diode IV curve, current initially remains constant but rises as voltage increases to 1.8 volts. Here, the value may vary a little. |
| 05:40 | Let's connect white LED in the circuit. |
| 05:44 | On the Plot window, click on EXPERIMENTS button. Select Diode IV. |
| 05:51 | On EYES:IV characteristics window, click on START button.
In the diode IV curve, current initially remains constant but rises as voltage increases to 2.6 volts. |
| 06:05 | Now, we will demonstrate 180 degree out of phase sine waves. |
| 06:10 | We can do this by inverting the output of SINE using an amplifier. Here, we are using 51K resistor for the amplification. |
| 06:21 | I will explain the circuit connections. |
| 06:24 | A1 is connected to SINE.
51K resistor is connected between SINE and IN. OUT is connected to A2. |
| 06:35 | This is the circuit diagram. |
| 06:37 | Let's see the result on the Plot window. |
| 06:40 | On the Plot window, click on A1 and drag to CH1. A1 is assigned to CH1. |
| 06:49 | Click on A2 and drag to CH2.
A2 is assigned to CH2. |
| 06:54 | Move the mSec/div slider to adjust the waves. Two Sine waves differing in phase by 180 degree are generated. |
| 07:04 | Click on CH1 and drag to FIT.
Click on CH2 and drag to FIT. |
| 07:10 | Voltage and frequency values are displayed on the right side. |
| 07:15 | Right-click on CH1. Voltage, frequency & Phase shift values are displayed at the bottom of the window. |
| 07:25 | Now, we will plot transistor CE (collector emitter) characteristic curves. |
| 07:31 | Please use 2N2222, NPN transistor. Solder the wires of the transistor so that transistor can be connected properly to the ExpEYES kit. |
| 07:44 | I will explain the circuit connections.
SQR1 is connected to 200K resistor. 200K resistor is connected to base of the transistor. |
| 07:56 | PVS is connected to collector using a 1K resistor.
IN1 is connected between 1K resistor and collector. |
| 08:06 | Emitter is connected to GND (ground).
100uF (micro farad) capacitor is connected between 200K resistor and GND. This is the circuit diagram. |
| 08:18 | Let's see the result on the Plot window. |
| 08:21 | On the Plot window, Set PVS value as 3 volts. PVS is set to 3 volts to provide internal voltage. |
| 08:31 | Click on EXPERIMENTS button and select Transistor CE. |
| 08:37 | EYES Junior: Transistor CE characteristics and Schematic windows open.
Schematic window shows circuit diagram. |
| 08:47 | On the EYES Junior: Transistor CE characteristics window, change the base voltage to 1 Volt. |
| 08:55 | Click on START button. Collector current increases and becomes constant.
Collector current is close to 0.3 mA. Base Current is 2uA(micro ampere). |
| 09:10 | Change the base voltage to 2 Volts and click on START button. Collector current is 1.5 mA |
| 09:19 | Base Current is 7uA(micro ampere). |
| 09:23 | Change the base voltage to 3V and click on START button. Collector current is 2.7mA |
| 09:33 | Base Current is 12uA(micro ampere). |
| 09:37 | Let's summarize. |
| 09:38 | In this tutorial, we have studied:
Working of PN Junction diode Diode as rectifier Diode IV characteristics LED IV characteristics Out of Phase inverting amplifier and Transistor CE. |
| 09:58 | As an assignment-
Measure the intensity of light and its variation from the source. This is the circuit diagram. The output should look like this. |
| 10:13 | This video summarizes the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it. |
| 10:21 | We conduct workshops using Spoken Tutorials and give certificates. Please contact us. |
| 10:28 | Spoken Tutorial project is funded by NMEICT, MHRD, Government of India. |
| 10:34 | This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi.
Thank you for joining. |
