CEC 220 Digital Circuit Design Implicants Wed, Sept. 23 CEC 220 Digital Circuit Design Slide 1 of 10
Lecture Outline Wed, Sept. 23 CEC 220 Digital Circuit Design Implicants Prime Implicants Essential Prime Implicants Slide 2 of 10
Four Variable Karnaugh Maps Implicants and Prime Implicants Wed, Sept. 23 CEC 220 Digital Circuit Design Implicants A single 1 or group of 1’s which can be combined to form a simpler term is called an implicant AB CD Slide 3 of 10
Four Variable Karnaugh Maps Implicants and Prime Implicants Wed, Sept. 23 CEC 220 Digital Circuit Design Prime Implicants An Implicant which can NOT be combined into another block is called a prime implicant AB CD Slide 4 of 10
Four Variable Karnaugh Maps Implicants and Prime Implicants Wed, Sept. 23 CEC 220 Digital Circuit Design Prime Implicants An Example AB CD All Prime Implicants: Min SOP Expression: Not all Prime Implicants are essential!! Slide 5 of 10
Four Variable Karnaugh Maps Implicants and Prime Implicants Wed, Sept. 23 CEC 220 Digital Circuit Design Essential Prime Implicants If a minterm is covered by only one prime implicant then that prime implicant is an essential prime implicant. AB CD Essential Prime Implicants? Min SOP Expression: Essential Prime Implicants MUST be included in the min SOP expression Slide 6 of 10
Karnaugh Maps Flowchart for Determining the min SOP Expression Wed, Sept. 23 CEC 220 Digital Circuit Design All uncovered 1’s checked? Are the chosen 1 and its adjacent 1’s and X’s covered by a single term? Are the chosen 1 and its adjacent 1’s and X’s covered by a single term? Find a minimum set of prime implicants which cover the remaining 1’s on the map. Find a minimum set of prime implicants which cover the remaining 1’s on the map. That term is an essential prime implicant. Circle it. Find all adjacent 1’s and X’s. Choose a 1 which has not been covered. yes no Start Slide 7 of 10
Karnaugh Maps Flowchart for determining the minimum SOP Wed, Sept. 23 CEC 220 Digital Circuit Design An Example Essential Prime Implicants: Slide 8 of 10
Karnaugh Maps Flowchart for determining the minimum SOP Wed, Sept. 23 CEC 220 Digital Circuit Design An Example Essential Prime Implicants: Slide 9 of 10
Next Lecture Wed, Sept. 23 CEC 220 Digital Circuit Design Multi-Level Gate Circuits Slide 10 of 10