NAME: _________________________________EXPERIMENT 3: Basic TTL Logic Gates (1 week)EE 110 Lab Experiment #3 Fall 2009NAME: _________________________________EXPERIMENT 3: Basic TTL Logic Gates (1 week)The purpose of this laboratory is to learn to use TTL logic gates and understand the basic logic functions ofAND, OR and NOT. Students will work individually.Background:The following diagrams illustrate the pinouts of several TTL devices we have in stock. These integratedcircuits are in Dual In-line Packages (DIP), consisting of a central case with two rows of pins. Seen fromthe top (i.e., the pins pointing away from you), look for the dent or notch at one end. This notch indicatesthe origin for pin numbering. Pins are numbered consecutively, going counterclockwise from the notch.In all cases, pin 7 must connect to GND and pin 14 to the +5V power supply. Without proper power and ground connections, the device will not function. DO NOT wire these backwards – you will destroy the part!Reminder: As you do this lab, please make sure that you follow every step as specified, and that you fill in all tables and questions. Please read each part of the lab carefully as you are about to begin that portion. This labrequires a TA signature at the end, verifying that all your circuits work as expected. As you finish each part of the lab, be sure to leave that circuit and all its connections on your protoboard, so that you can show the TA that it works as expected at the end of the lab. This lab has 7 pages – please be sure to check the back page of the lab. This page includes verification of your lab results by the lab TA, and your conclusions and comments about this lab.PART 1 - NOT gateProcedure: 1. In the space below, labeled Figure 1, draw a logic diagram of the NOT gate. Hint: Look at theinidividual NOT gates shown in the 74LS04 chip. Include input and output lines; you can drawthem as straight lines.2. Label the gate with the 7400 family part number you plan to use; for the NOT gate, this would bea 74LS04 device.2-1EE 110 Lab Experiment #3 Fall 20093. Label the input and output of each gate with the pin numbers you wish to use for the chosendevice. The 74LS04 device includes 6 NOT gates, each with one input and one output; you coulduse input pin 1 and output pin 2 for one gate, or input pin 3 and output pin 4. Remember to useinput and output for the same gate.Figure 1: Logic diagram of NOT gate4. Now build this logic circuit on your proto board. Use 22-gauge wire to make all connections. a. Make sure power is turned off. Plug the chosen device into your proto board in the correctplaces (use the area on the left side of the proto board). Wire each part to power andground as required. (Connect to the power busses you configured in the first labexperiment. Use RED wires for your connections to the +5V supply and BLACK wiresfor the GND connections.) Double-check your pin numbers for the power and groundwires; you don’t want to wire these backwards! It pays to take the time to be careful. Ifyou are not sure how to wire up either the power bus (it is probably already wired up, butcheck to be sure) or the chip, please ask for help from the TA or lab instructor beforepowering up your lab trainer. You can destroy either the chip if power and GND arereversed, or the trainer if there is a short (power connected to directly to GND).b. Connect the output to the leftmost of the 8 single LEDs above your proto board. It shouldbe labeled LED 7. Use any wire color other than red or black for your connection. c. Wire the input to switch SW0. Again, use any wire color other than red or black. It helpsto use the same color wire for both input and output; that way, you can keep track of thesignal path.5. Check your wiring. Make sure you have not connected a gate output directly to a switch. Makesure your power connections (RED) and ground connections (BLACK) are correct to the chip. Besure that the power busses are wired correctly. Make sure your chip is not in upside-down.6. Fill out the truth table in Table 1 below with possible input values of A in column 1, and the outputvalues you expect to see for a NOT gate, based on the input values for A, listed in column 2.Remember, A is a binary variable. A will be controlled by switch SW0.7. Now power on your lab trainer. Set switch SW0 to 0. Is LED 7 lighted or not? Decide whether alighted LED means a 0 or 1, and put the appropriate value into Table 1 as observed output, incolumn 3, in the appropriate row given that SW0 is set to 0. 8. Now move switch SW0 to 1. Is LED 7 lighted or not? Again put the appropriate value for yourobserved output, as indicated by LED 7, in column 3, again in the appropriate row for SW0 set to1. Do your observed outputs match your expected outputs? If they don’t, consider the followingpossibilities, and try to determine what the problem is and fix it:a. Input not connected properly; check input with logic probe to be certain that SW0 is set tothe value you expect. It’s also possible the switch SW0 is not working, and you candetermine that by checking SW0 output also.b. Output not connected properly to LED 7; check output with logic probe. If the output iscorrect, perhaps your wire connection to the LED 7 terminal is not solid. Does the wireend look like it might break off? If so, use another wire. If not, try pushing the wire into2-2EE 110 Lab Experiment #3 Fall 2009the LED 7 terminal a little further. Or switch the wire to another LED. If the LED stilldoes not display the value you expect, consider whether you have made the correctdecision as to whether a lighted LED means a 0 or a 1. c. Chip not powered correctly; check pin 7 and pin 14 with logic probe to be certain they areat GND and +5 V, respectively. If they are not, check to see if you have:i. Connected GND and/or +5 V to the wrong pin location (they are switched, are offby one pin, or chip is upside down). If so, change them quickly. Having thepower and ground switched will cause the chip to overheat and eventually destroythe chip.ii. Wired the power busses correctly; check both the +5 V and GND busses to becertain they are at the correct voltage.iii. Make sure the lab trainer power switch is turned on.d. Expected output values are incorrect. The NOT gate output inverts the input, so theoutput value should be the complement (or the opposite) of the input