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HD74HC108 Datasheet, PDF (4/7 Pages) Hitachi Semiconductor – Dual J-K Flip-Flops (with Preset, Common Clear and Common Clock)
HD74HC108
Switching Characteristics (CL = 50 pF, Input tr = tf = 6 ns)
Item
Maximum clock
frequency
Propagation delay
time
Pulse width
Setup time
Hold time
Removal time
Output rise/fall
time
Input capacitance
Symbol VCC (V)
fmax
2.0
4.5
6.0
tPLH, tPHL 2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
tw
2.0
4.5
6.0
tsu
2.0
4.5
6.0
th
2.0
4.5
6.0
trem
2.0
4.5
6.0
tTLH, tTHL 2.0
4.5
6.0
Cin
—
Ta = 25°C
Ta = –40 to +85°C
Min Typ Max Min Max Unit
Test Conditions
—— 6
—
5 MHz
— — 30
—
24
— — 35
—
28
— — 150 —
190 ns Clock to Q or Q
— 20 30
—
38
— — 26
—
33
— — 140 —
175 ns Clear to Q or Q
— 18 28
—
35
— — 24
—
30
— — 140 —
175 ns Preset to Q or Q
— 16 28
—
35
— — 24
—
30
80 — — 100
— ns
16 7 —
20
—
14 — —
17
—
100 — — 125
— ns
20 2 —
25
—
17 — —
21
—
5 ——
5
— ns
5 –1 —
5
—
5 ——
5
—
100 — 125 —
— ns
20 –2 25
—
—
17 — 21
—
—
— — 75
—
95 ns
— 5 15
—
19
— — 13
—
16
— 5 10
—
10 pF
Test Circuit
VCC
VCC
Input
Pulse generator
Zout = 50 Ω
Input
Pulse generator
Zout = 50 Ω
Preset
Output
J
Clock
Q
Output
CL = 50 pF
K
Q
Clear
CL = 50 pF
Note: CL includes the probe and jig capacitance.
Rev.2.00, Oct 11, 2005 page 4 of 6