2 votes 2 votes A JK flip flop has propagation delay of 13ns. what is the largest MOD ripple counter that can be constructed using such flip flop and can be operated upto 10MHZ? 1.MOD - 32 2 MOD - 64 3 MOD - 128 4 MOD - 256 focus _GATE asked Jun 20, 2015 focus _GATE 891 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 6 votes 6 votes For ripple counter T(clock) >= N*(propagation delay of FF) // N is no of FF as the output from the final flipflop comes only after propagation delay of all n FFs. Frequency = 10MHz means T(clock) = 0.1 Micro second Apply formula, 0.1 micro second >= N* 13ns Max value of N is 7.. With 7 Flip Flop, max mod value is 128.. Ref: http://mti.kvk.uni-obuda.hu/adat/tananyag/digit2/angolkepzes/dt_2_lecture04w.pdf Digvijay Pandey answered Jun 20, 2015 • selected Jun 20, 2015 by Digvijay Pandey Digvijay Pandey comment Share Follow See all 2 Comments See all 2 2 Comments reply Pankajgate16 commented Jun 23, 2015 reply Follow Share Yes, 128 IS CORRECT 0 votes 0 votes Kaluti commented Oct 4, 2017 reply Follow Share the above link is not working 0 votes 0 votes Please log in or register to add a comment.