5.5 Switching Characteristics

(2)

Input tt = 6ns. Unless otherwise specified, CL = 50pF

PARAMETER

VCC (V)

25°C

-40°C to 85°C

-55°C to 125°C

UNIT

MIN

TYP

MAX

MIN

MAX

MIN

MAX

HC TYPES

tpd

Propagation delay

A to B

B to A

2

90

115

135

ns

4.5

7

(1)

18

23

27

6

15

20

23

tpd

Propagation delay

Output High-Z

To high level,

low level

2

150

190

225

ns

4.5

12

(1)

30

38

45

6

26

33

38

tpd

Propagation delay

Output high level

Output lowe level to high Z

2

150

190

225

ns

4.5

12

(1)

30

38

45

6

26

33

38

tt

Output transition time

2

60

75

90

ns

4.5

12

15

18

6

10

13

15

Ci

Input Capacitance

10

10

10

10

pF

CO

Three-state output

capacitance

20

20

20

pF

Cpd

Power dissipation capacitance

(3) (4)

5

38

pF

HCT TYPES

tpd

Propagation delay

A to B

B to A

4.5

9

(1)

22

28

33

ns

tpd

Propagation delay

Output High-Z

To high level,

low level

4.5

12

(1)

30

38

ns

tpd

Propagation delay

Output high level

Output lowe level to high Z

4.5

12

(1)

30

38

ns

tt

Transition times

4.5

12

15

ns

Ci

Input capacitance

10

10

10

pF

CO

Three-state output

capacitance

20

20

pF

Cpd

Power dissipation capacitance

(3) (4)

5

41

pF

(1)

Typical value tested at 5V, CL = 15pF.

(2)

For details on CMOS power calculation see, SCAA053B

(3)

CPD is used to determine the dynamic power consumption, per channel

(4)

PD = VCC 2 fi (CPD + CL) where fi = Input Frequency, CL = Output Load Capacitance, VCC = Supply Voltage.

CD54HC640, CD74HC640, CD54HCT640, CD74HCT640

SCHS192C – NOVEMBER 1998 – REVISED JULY 2022

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