Digital Electronics: Principles, Devices and Applications

Flip-Flops and Related Devices 409(a) set-up time and hold time;(b) propagation delay;(c) maximum clock frequency.7. Draw the truth table for the following types of flip-flop:(a) a positive edge-triggered J-K flip-flop with active HIGH J and K inputs and active LOWPRESET and CLEAR inputs;(b) a negative edge-triggered J-K flip-flop with active LOW J and K inputs and active LOWPRESET and CLEAR inputs.8. What is meant by the race problem in flip-flops? How does a master–slave configuration help insolving this problem?9. Differentiate between a D flip-flop and a D latch.10. Draw the function table for (a) a negative edge-triggered D flip-flop and (b) a D latch with anactive LOW ENABLE input.11. With the help of a schematic arrangement, explain how a J-K flip-flop can be used as a (a) a Dflip-flop and (b) a T flip-flop.12. With the help of a suitable circuit, briefly explain how a D flip-flop can be used to detect thesequence of occurrence of edges of synchronous inputs.Problems1. A 100 kHz clock signal is applied to a J-K flip-flop with J = K = 1.(a) If the flip-flop has active HIGH J and K inputs and is negative edge triggered, determine thefrequency of the Q and Q outputs.(b) If the flip-flop has active LOW J and K inputs and is positive edge triggered, what should thefrequency of the Q and Q outputs be? Assume that Q is initially ‘0’.(a) Q output = 50 kHz, Q output = 50 kHz;(b) both outputs remain in a logic ‘0’ state2. In a Schmitt trigger inverter circuit, the two trip points are observed to occur at 1.8 and 2.8 V. Atwhat input voltage levels will this device make (a) HIGH-to-LOW transition and (b) LOW-to-HIGHtransition?(a) 2.8 V; (b) 1.8 V3. In the case of a presettable, clearable J-K flip-flop with active HIGH J and K inputs and activeLOW PRESET and CLEAR inputs, what would the Q output logic status be for the following inputconditions, assuming that Q is initially ‘0’, immediately after it is clocked?(a) J = 1,K = 0, PRESET = 1, CLEAR = 1;(b) J = 1,K = 1 , PRESET = 0, CLEAR = 1;(c) J = 0, K = 1 , PRESET = 1, CLEAR = 0;(d) J = K = 0, PRESET = 0, CLEAR = 1.(a) 1; (b) 1; (c) 0; (d) 1