1. Analysis of Synchronous Sequential Circuits
Chapter 8
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2. Synchronous Sequential CircuitsX1 Z1
Combinational
Circuit X2 . .. Zm . .. Xn Y1
Flip Flops . .. . .. Yr
Clock
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3. Synchronous Sequential Circuits
Zi = fi(X1, X2, …,Xn, Y1, Y2, …,Yr, )
Yi = gi(X1, X2, …,Xn, Y1, Y2, …,Yr, )
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4. Synchronous Sequential Circuits
1. Derive the output equations
2. Derive the F/Fs input equations
3. Derive the next state equations
4. Derive the CKT's State Transition Table
State table give a complete description of circuits behavior
5. State diagram
6. Get timing diagrams
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5. Example 1
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6. Example1 Cont. Step 1: Z = AX' + BX' Step 2: DA = AX + BX DB = A'X
Step 3: D F/F characteristic eq.
Q(t+1) = D
==> A(t+1) = AX + BX
B(t+1) = A'X
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7. Example Cont.
Step 4: State Transition Table
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8. Timing Diagram
Assume Input Sequence:
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9. Example 2
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10. Example2: Analysis Preliminary: inputs: X outputs: Z
State Variables: A & B
Note: Moore circuit
(1) output equations:
Z = AB'
(2) Flip Flop Input Equations:
JA = B KA = BX'
JB = X' KB = AX' + A'X
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11. State Transition Table
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12. Traffic Light Controller
You are to design a traffic light controller to control an intersection. The intersection consists of two streets, one running north-south (called NS) and the other running east-west (called EW). The circuit has to control one traffic lights on the NS street, one traffic light on the EW street. 
Each of the traffic signals consists of a red, yellow, and green light. Each of the traffic signals cycles through red, green, yellow, and back to red. When one traffic signal is green or yellow, the other is red. When one traffic light is red, the other is greed or yellow. To simplify the design and shorten the experimentation time, we will set the green, yellow, and red time periods to 4, 1, and 5 seconds, respectively.
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