Draw the logic circuit to represent the Boolean expression

1. (a) By using a truth table show that the expressions


are equivalent.

(b) Show by plotting truth tables that


2. (a) Draw the logic circuit to represent the following Boolean expression using only NAND gates.


(b) Draw the logic circuit to represent the following Boolean expression using only NOR gates.


Indicate the outputs of each gate.

3. In the ladder diagram shown in FIGURE 1, Y006 is a lamp, X and R references are relay contacts. Write down the Boolean expression for the lamp to light.

2131_ladder diagram.jpg

FIG. 1

4. (a) Add the following HEX numbers converting to binary. Express the answer in HEX.

(i) 08 + 03

(ii) 0ABC + DA0E.

(b) Write down the 2's complement of:

(i) 00000001

(ii) 00111100

(c) Convert the following denary numbers to 8 bit binary numbers and evaluate using the '2's' complement' method. Leave your answers in binary form.

(i) 17 - 8

(ii) 97 - 125

(d) (i) Write down the bcd form of decimal 845.

(ii) Convert the denary number 818 first to hexadecimal then to binary.

Show all working.

5. State three disadvantages of relays when compared with the use of PLCs in process control circuits.

6. (a) State what is meant by input and output interfaces in relation to PLCs.

(b) State briefly what the function of interfaces is in relation to the different types of process signal.

(c) The diagram of FIGURE 2 shows a bi-directional opto coupler input interface circuit. When a supply voltage of 20 V is applied the LED carries a current and 2 V is dropped across it. Calculate the value of the LED current and the value of current through the 3 k? resistance.


FIG. 2

(d) The circuit shown in FIGURE 3 is part of the interface of a relay output module. Ib is 1 mA and VCC is 9 V. The relay requires a minimum of 50 mA to energise.

Complete the values of the assumptions listed below in order to calculate:

- voltage across R1
- value of R1

- voltage across the relay coil

- voltage across R2
- value of R2
- collector of current Ic.


Logic '1' = V

Logic '0' = V

Transistor forward current gain hfe =

LED current = 10 mA

LED voltage drop at 10 mA = V

Base/emitter voltage = V

Collector emitter voltage when transistor is on = 1 V



FIG. 3

Order Assignment gulfassignmenthelp Rated 4.9 / 5 based on 22789 reviews.
  • Abdullah

    Hey just wanted to inquire if you provide professional assignment help services in Gulf countries and if you do then what are the charges for assignment writing. Do you charge on the basis of the quality of assignment or its length? I am asking all these questions because I am a student studying in UAE and I am desperate to get some assistance with my homework. I have a lot of pending assignments which I am unable to write. The reason behind this is that I got lazy for a short amount of time and new assignments kept coming in and couldn’t manage all those assignments at once. The most recent assignment I got is based on questions on Electronics and circuit theory as you have also answered in the above article. So do you provide UAE assignment help or Gulf assignment help for students like me? I know that you will charge me for this and I am fine with paying money because I just want to get out of this problem. My whole schedule is disturbed because I can't decide which assignment to do first and I also don’t have time for studies. So please help me with your assignment writing services

  • Abeera

    Hey. I was looking for some assistance to complete my homework. The module you have provided here is based on the same theme on which I have an assignment to write. I am a student who is doing diploma in Electronics discipline from a university in the United Arab Emirates. And I get too confused on assignments like these because the circuits are too complicated to be understood by me. That is why I was searching for Gulf assignment help at a low price. I know that you are a professional homework help service and that is why I wanted to know that if you have expert tutors to assist me on my assignment. And could you also tell me that what other subjects you cover under this service? And what if I order multiple assignments from your website then will I get a discount on the price. I know that is a lot of queries but I seriously need your help with this assignment.


Seeking Trusted Advice of High Skilled Tutors for Gulf Assignments? Order Now