RS bistable, clocked RS-bistable, JK latch, D latch, T Latch

1. Flip Flop
Nugroho Adi Pramono
nugnux@gmail.com,aravir@me.com
http://aravir-rose.blogspot.com/p/digital

2. “But, before that…”

3. Real Gate

4. Interfacing
It must work
It must NOT damage other circuit

5. How fast?
How much current?
What voltage
Things we may have overlooked

6. How Fast?
As fast as slowest chip
(chip to chip)

7. How Fast?
Irrelevant
(chip to something else)

8. How much current?

9. What voltage

10. Others Things

11. Switch Bounce

12. Switch Bounce

13. Smile or Smoke?

14. Smile or Smoke?

15. Smile or Smoke?

16. Power Supply

18. Sequential Logic

19. Combinational Logic
some gates
some inputs
output (with certainty)

20. Sequential Logic
inputs
gates
previous state

21. Sequential Logic
tombol televisi
saklar lampu
bel pintu

22. Switches
Latching
non-Latching

23. Switches

25. RS bistable
SR bistable
RS Flip-Flop
SR Flip-Flop
RS Latch

26. RS bistable

27. RS bistable

28. NAND Latch

29. (1) = 1
(3) = 0 atau 1 tergantung (2)
(5) = 0
(6) = 1 (sifat NAND)
(6) — (2)
gate A punya input 1 semua
(3) = 0
(4) = 0
Q = 0 (reset)
Q’ = 1
S = 1, R = 0

30. (1) = 0
(3) = 1
gate B punya input 1 semua
(3) — (4) = 1
(5) = R = 1
(6) = 0
Q = 1 (set)
Q’ = 0
S = 0, R = 1

31. “nol untuk menyalakan”
–Active Low Input
Dan dia hidup bahagia selama-lamanya...

32. (1) = 0
(3) = 1
(5) = 0
(6) = 1
Q = 1
Q’ = 1
Forbidden
S = 0, R = 0

33. S = 1, R = 1
Tak ada yang terjadi

36. Switch Debouncer

38. Alternatif dari
adalah

40. Tentukan tabel kebenarannya

41. Testing the Glitch
Catcher

42. latch
dapatkah mendeteksi perubahan logic state?
pada durasi yang sangat pendek?
50 ns

43. mudah
gunakan switch
tekan!
pasti memantul

44. mudah lagi
gunakan switch debouncer
tekan!
tak cukup cepat, 10 ms
alt -> gunakan gerbang logika

45. Transition effects
ubah input pada gerbang NOT
NOT hanya akan membalik sinyal

47. Sepertinya baik-baik saja

48. Bagaimana jika intervalnya 10 ns?

50. Perubahan output ternyata tidak langsung
memiliki waktu tunda
waktu yang diperlukan tegangan untuk berjalan
melalui gate
transition/propagation time

51. untuk sesaat, sekitar 10 ns, input dan output
memiliki logika yang sama (pada NOT)

52. Apakah bermasalah?

54. salah satu input dilewatkan ke inverter
input XNOR selalu memiliki nilai yang berlawanan
output XNOR selalu nol

56. Clocked Bistable

57. Asynchronous
Go when you like
Operate immediately when input applied
All gates
RS bistable

58. We don’t Always Want This
alarm berbunyi sesegera setelah diset
pesawat take-off segera setelah pilot datang
koki langsung masak segera setelah bahan datang

59. Synchronous
Wait until you told

60. Clocked RS Bistable

61. Clocked Input

62. Clocked Input

63. Clocked Input

64. “4 NAND gate, 1 chip 74xx00”
–Johnny Appleseed

65. JK Latch

70. The Golden Rules of JKs
If J and K different, the Q is always the same as J
If J and K are 0, nothing happens
If J and K are 1, the output toggles

71. Apa Gunanya Clock?
menentukan respon terhadap input

72. When does the Clock Tick?
input harus ada sebelum perubahan clock
setup time 20 ns
hold time 0 s (often)

73. Negative Edge Triggered
(trailing edge triggered)
the action occurs at the end of the clock pulse
just as its logic level chages from 0 to 1
symbol > o

74. J=1, K=1

75. Positive Edge triggering
(rising/leading edge triggering)
kebalikan dari trailing edge triggered

76. J=1, K=1

77. J=1, K=1

78. Pulse Triggering
(master-slave design)
mirip trailing edge JK

79. Pulse Triggering
1. The JK inputs and the Q and NOT Q outputs are isolated.
2. As soon as the leading edge of the clock pulse reaches
logic 1, the data enters and is stored inside the JK.
3. At the end of the clock pulse, when the falling edge
leaves the logic 1 level, the J and K inputs are
disconnected preventing any latecomers from getting in.
4. The data is transferred to the Q and NOT Q output

80. Pulse Triggering

81. Pulse Triggering

82. D flip-flop

83. D flip-flop

84. D flip-flop

85. D flip-flop

86. D flip-flop

87. D flip-flop

88. T flip-flop

89. T flip-flop

90. T flip-flop

91. Selesai
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