SN54-74LS90 ON Semiconductor, SN54-74LS90 Datasheet - Page 6

• Manufacturer Part Number: SN54-74LS90
• Description: DECADE COUNTER; DIVIDE-BY-TWELVE COUNTER; 4-BIT BINARY COUNTER
• Manufacturer: ON Semiconductor

AC CHARACTERISTICS
AC SETUP REQUIREMENTS
RECOVERY TIME (t rec ) is defined as the minimum time required between the end of the reset pulse and the clock transition from HIGH-to-LOW in order to recognize
and transfer HIGH data to the Q outputs
f MAX
f MAX
t PLH
t PHL
t PLH
t PHL
t PLH
t PHL
t PLH
t PHL
t PLH
t PHL
t PLH
t PHL
t PHL
t W
t W
t W
t W
t rec
S
S
Symbol
S
S
Symbol
MR & MS
b l
b l
b l
b l
CP
Q
*The number of Clock Pulses required between the t PHL and t PLH measurements can be determined from the appropriate Truth Tables.
CP 0 Pulse Width
CP 1 Pulse Width
MS Pulse Width
MR Pulse Width
Recovery Time MR to CP
CP 0 Input Clock Frequency
CP 1 Input Clock Frequency
Propagation Delay,
CP 0 Input to Q 0 Output
CP 0 Input to Q 3 Output
CP 1 Input to Q 1 Output
CP 1 Input to Q 2 Output
CP 1 Input to Q 3 Output
MS Input to Q 0 and Q 3 Outputs
MS Input to Q 1 and Q 2 Outputs
MR Input to Any Output
t PHL
1.3 V
Figure 2
t W
SN54/74LS90 SN54/74LS92 SN54/74LS93
(T A = 25 C, V CC = 5.0 V, C L = 15 pF)
P
P
Parameter
P
P
Parameter
1.3 V
(T A = 25 C, V CC = 5.0 V)
1.3 V
t rec
*CP
Q
1.3 V
t PHL
1.3 V
FAST AND LS TTL DATA
1.3 V
AC WAVEFORMS
Min
32
16
Min
15
30
15
15
25
Figure 1
LS90
LS90
5-6
Typ
1.3 V
10
12
32
34
10
14
21
23
21
23
20
26
26
Max
t W
Q 0 Q 3
Max
16
18
48
50
16
21
32
35
32
35
30
40
40
(LS90)
MS
CP
1.3 V
Min
32
16
Min
15
30
15
25
t PLH
1.3 V
1.3 V
t PLH
Limits
Limits
LS92
LS92
Typ
10
12
32
34
10
14
10
14
21
23
26
Max
t W
Max
Figure 3
16
18
48
50
16
21
16
21
32
35
40
1.3 V
Min
32
16
1.3 V
Min
15
30
15
25
t rec
LS93
LS93
Typ
10
12
46
46
10
14
21
23
34
34
26
1.3 V
Max
Max
16
18
70
70
16
21
32
35
51
51
40
MHz
MHz
U i
U i
Unit
U i
U i
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns