SEMICONDUCTOR DEVICES

SEMICONDUCTOR DEVICES - INTRODUCTION Through this lab...

This preview shows pages 1–6. Sign up to view the full content.

1 INTRODUCTION Through this lab experiment we were able to measure the forward and the reverse biased current and voltage characteristics for the P-N junction diode. And also we learnt how to use the oscilloscope in the X-Y mode to plot the current—voltage curve for the diode. By the experiment we did we understood how the temperature affects the operational characteristics of a diode. As we were practiced with using the oscilloscope in last lab we could easily gain the results as desired. APPARATUS Parts and Equipment: Resistors: 1 kΩ Diode 1N4007 ( or equivalent) - 2 Transformer: Step-down transformer, approximately 12V secondary voltage High impedance digital multi-meter Oscilloscope Soldering iron DC power supply Breadboard and wires OBSERVATIONS Procedure # 1 Circuit 1 We built the circuit-1 as we were asked to do. And then we measured each electronic component by using DMM and recorded as follows, Figure 2.1 Component Nominal values Measured values V S 15.0V 15.02V R 1kΩ 0.99kΩ Table 2.1 Then we measured the voltages across the diode and the resistor, V S = 15V Voltage across Measured Diode-V D 0.7V Resistor-V R 14.32V Table 2.2 D

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 Next we set the voltage of the source to -15V and measure the voltages across the resistor and the diode, V S = -15V Voltage across Measured Diode-V D 0.7V Resistor-V R 14.32V Table 2.3 Procedure # 2 Circuit 2 Figure 2.2 We built the second circuit as shown above to check the dynamic characteristics of the diode. Therefore we use a 12.6V center tapped transformer as the voltage supply to the circuit. Component Nominal values Measured values V S 12.6V 12.77V R 1kΩ 0.99kΩ Table 2.4 a) Calibrating the oscilloscope before connecting the oscilloscope to the circuit we should calibrate the oscilloscope by connecting each channel to the probe compensation terminal. Figure No Figure 2.3
3 Then we will be able to see compensated wave on the screen similar to the Figure Figure2.4 After getting the above signal we have to turn the small knob which is in the probe using the tool that we get with the probe (Figure 2.5) and change the wave to a square wave form until the wave get perfectly compensated/calibrated .(Figure No2.4) Figure 2.5 After calibrating the oscilloscope we pressed the AUTO Set button before we connect the probes to the nodes of the circuit.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
4 b) Then we connected the probes to the nodes as required and the observed the graph from the oscilloscope. X 1 = 680mV X 2 = 560mV Figure 2.6 Procedure # 3 Diode voltage at the 16mA = 680mV Lowest voltage observed at 16mA = 560mV ±²³´µ¶·¸µ¹µ´º²¶»¼³´¸»´±²³´½¾¿±¶¼³´¾À´±²³´Á¸¾Á³ Â ÃÄÅÆ Ç ÈÄÆÉµÊ ´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´Â ËÌÆµÊ
POST LAB EXERCISE 1. What is the normal forward operating voltage of a standard silicon diode? 0.7v is the operating voltage of a standard silicon diode

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/30/2011 for the course MECHATRONI EN11ME2050 taught by Professor Perera during the Spring '11 term at Asian Institute of Technology.

Page1 / 11

SEMICONDUCTOR DEVICES - INTRODUCTION Through this lab...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online