advertisement

Fatih University Computer Engineering Department CENG 203/B Digital Systems - Midterm 7 December 2009 1 hour 30 minutes Name - Surname: Student No: Signature: 1. (20p) Show an algebraic expression for the following circuit. Reduce it to a minimum sum of products expression (2 terms, 4 literals.) c a b' g c' d 2. (20p) For the function, F, shown find a minimum sum of products expression and a minimum product of sums expression (spare map shown). WX YZ 00 00 01 11 10 1 01 1 11 1 X 10 1 X 00 01 11 10 X 00 X 01 11 1 1 10 3. (20p) The following function is the only minimum sum of products expression. Implement it using only two-input NAND gates. No gate may be used as a NOT gate. Show both the block diagram and the equation. Assume that all inputs are available both uncomplemented and complemented. (Full credit for 15 gates; partial credit if you use one three-input gate.) F = B' C' D' E + B C D' + A' B' C + A' B C' + A' B' E' + A D E' 1 4. (20p) List all prime implicants, indicating which are essential. Find all 4 minimum sum of products expressions. ab cd 00 01 11 10 00 1 01 1 11 10 1 1 1 1 1 1 1 1 1 5. (20p) Create an eight-way multiplexer using 2-way multiplexers as shown below: Attention! Notes are not allowed within your sight! Cell phones must be turned off or silent and are not allowed to be on the desk. You are not allowed to use calculator, and pen but pencil only! No exchange of eraser! Also forbidden to leave the exam on or before the one hour time from the start. Good Luck! Assistant Professor Dr. Ihsan Omur Bucak 2