1. Answer to exercises(3) P185, 3.11 (a) Circuit diagram C B V DD Z Q6Q6 Q4Q4 Q1Q1 Q3Q3 Q5Q5 A Q2Q2 A B C Q1 Q2 Q3 Q4 Q5 Q6 Z L L L off on off on off on 1 L L H off on off on on off 0 L H L off on on off off on 0 L H H off on on off on off 0 H L L on off off on off on 0 H L H on off off on on off 0 H H L on off on off off on 0 H H H on off on off on off 0 (b) Function table (c) Logic symbol A B Z C

2. Answer to exercises(3) P185, 3.13 (a) Circuit diagram A B Q1 Q2 Q3 Q4 Q5 Q6 Z L L off on off on on off 0 L H off on on off off on 1 H L on off off on off on 1 H H on off on off off on 1 (b) Function table (c) Logic symbol A B Z B A V DD Z Q4Q4 Q2Q2 Q1Q1 Q3Q3 Q5Q5 Q6Q6

3. Answer to exercises(3) P185, 3.16 (a) Function table A B C DQ1 Q2 Q3 Q4 Q5 Q6 Q7 Q8Z L L L L L H L L H L L L H H L H L L L H L H H L L H H H off on off on off on off on on on off off off on off on off off on on off on off on on off on off off on on off off on off on off on on off on on off off off on on off off off on on off on on off on off on off 1000100010001000

4. Answer to exercises(3) (a) Function table(continuous) (b) Logic diagram A B C DQ1 Q2 Q3 Q4 Q5 Q6 Q7 Q8Z H L L L H L L H H L H L H H H H L L H H L H H H H L H H on off off on off on off on on off off on on on off off on off off on off off on on on off off on on off on off on off on off off on off on on off on off on on off off on off on off off off on on on off on off 1000000010000000 Z A B C D

5. Answer to exercises(3) P185, 3.17 (a) Function table A B C DQ1 Q2 Q3 Q4 Q5 Q6 Q7 Q8Z L L L L L H L L H L L L H H L H L L L H L H H L L H H H off on off on off on off on off on on off off on off on on off off on off on off on on off on off off on on off off on off on off on on off off on on off on off off on off on on off on off on off 1111111011111110

6. Answer to exercises(3) (a) Function table (continuous) A B C DQ1 Q2 Q3 Q4 Q5 Q6 Q7 Q8Z H L L L H L L H H L H L H H H H L L H H L H H H H L H H on off off on off on off on on off off on off on on off on off off on on off off on on off on off on off on off off on off on on off on off off on on off on off on off on off off on on off on off 1110111011101110 (b) Logic diagram A Z B C D

7. Answer to exercises(3) P186, 3.19 Solution DC noise margin=V OHmin -V IHmin =(V cc -0.5-0.1) -V IHmin  4.4V-3.5V=0.9V (HIGH-state) DC noise margin=V ILmax -V OLmax  1.5V-0.1V=1.4V (LOW-state) P186, 3.25 Solution According to Table 3-12 the I IH and I IL specifica- tions for 74LS00 are: I IHmax = 20  A, I ILmax = -0.4mA Assume standard 1.5V and 3.5V thresholds for LOW and HIGH.

8. Answer to exercises(3) P187, 3.36 Solution The hysteresis is V T+ -V T- =1.6V-1.3V=0.3V According to Table 3-8 the I OH and I OL speci- fications for 74FCT138T are: I OHmax = -15mA, I OLmax = 64mA 0.81.31.62.0 V IN V OUT o 5.0

9. Answer to exercises(3) P187, 3.39 Solution P187, 3.40 Solution The answer is the same as Drill 3.39. P187, 3.53 Solution DC noise margin=V OHmin -V IHmin  2.7V-2.0V=0.7V (HIGH-state) DC noise margin=V ILmax -V OLmax  0.8V-0.4V=0.4V (LOW-state)

10. Answer to exercises(3) P188, 3.56(a) Solution (a) 74HCT driving 74LS  For 74HCT, V OLmax =0.33V, V OHmin =3.84V For 74LS, V ILmax =0.8V, V IHmin =2.0V  DC noise margin=V OHminHCT -V IHminLS  3.84V-2.0V=1.84V (HIGH-state) DC noise margin=V ILmaxLS -V OLmaxHCT  0.8V-0.33V=0.47V (LOW-state)

11. Answer to exercises(3) P188, 3.56(a) Solution 74LS driving 74HCT  For 74LS, V OLmax =0.5V, V OHmin =2.7V For 74HCT, V ILmax =0.8V, V IHmin =2.0V  DC noise margin=V OHmin -V IHmin  2.7V-2.0V=0.7V (HIGH-state) DC noise margin=V ILmax -V OLmax  0.8V-0.5V=0.3V (LOW-state)

12. Answer to exercises(3) P188, 3.57(a) Solution (a) 74HCT driving 74LS  For 74HCT, I OLmaxT =4.0mA, I OHmaxT =-4.0mA For 74LS, I ILmax =-0.4mA, I IHmax =20  A In the LOW-state, no “ excess ” driving capability is available. In the HIGH-state, 190 inputs “ excess ” driving capability is available.

13. Answer to exercises(3) P190, 3.76 Solution P190, 3.91 Solution

14. Answer to exercises(3) (a) Truth table (continuous) W X Y ZF F 0 0 0 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 0 1 0 1 1 0 0 1 1 1 0001000100010001 1 0 0 0 1 0 0 1 1 0 1 0 1 1 1 1 0 0 1 1 0 1 1 1 1 0 1 1 0001111100011111 (b) Logic expression P191, 3.92 Solution

15. Answer to exercises(3) P191, 3.93 Solution P191, 3.94 Solution

16. Answer to exercises(3) P191, 3.96 Solution EN1 D1 Y1 EN2 D2 Y2 ENn Dn Yn I OH I IH I Leakage I IH I Leakage I OL I IL I Leakage I IL I Leakage I IL