QUESTION 1 [40 MARKS] (a) Read the following paragraph and fill in the blanks with suitable words from the given list. Digital techniques and systems have the advantage of being relatively much easier to design and having higher (1)_ - - programmability, noise immunity, easier storage of (2). and ease of fabrication in integrated form, leading to availability of more complex functions in a smaller size. The real world, however, is analogue. Most physical quantities - position, velocity, (3). force, pressure, temperature and flowrate, for example - are analogue in nature. That is why analogue variables representing these quantities need to be (4). or discretized at the input if we want to benefit from the features and facilities that come with the use of digital techniques. In a typical system dealing with analogue inputs and outputs, analogue variables are digitized at the input with the help of an analogue-to-digital converter block and (5). back to analogue form at the output using a digital-to-analogue converter block. [Adapted from Digital Electronics ; Principles, Devices and Application by Anil K. Maini] (List of words : bytes, transformed, acceleration, accuracy, digitized, reconverted, counter, resolution, data, package] (b) (6) Express the largest 16-bit binary number in hexadecimal number. (ii) What is the equivalent in decimal for the smallest number in an 8-bit signed 2's complement number? (iii) How many bits are needed to represent 1024j0- (c) (i) Draw the alternative symbols for 2-input NOR and AND gates. [2 marks] (ii) Show how a NOT function can be implemented using each of the following gates; 2-input NAND gate, 2-input X-OR gate and 2-input NOR gate. (d) Using Boolean algebra, prove if the following equations are true or not. (i) A+AB=AB A OB = B+ A.B (iii) A.B+AOB+cC=A+B (ii) (e) Simplify F(A,B,C.D) = E m (0,2,6,7,8,10,14,15) using Karnaugh map. (1) (6) Analyse the circuit in Figure 1 and write its truth-table. (ii) Suggest a suitable name for the circuit. F1 B Fo Figure I (i) State the difference between a combinational logic and a sequential logic. (ii) What distinguish a flip-flop from a latch? (iii) Explain why there exists illegal input for an R-S latch. (h) Three devices are given as follows: 2764 - 8K X 8 EPROM 2832 - 4K X 8 EEPROM 6264 - 8K X 8 SRAM Identify which of the above device/devices has/have the following characteristics; (i) 22 memory locations 13 address lines (ii) (iii) 8 outputs