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High Speed CMOS Logic – 74HC123

Rev 1.0

06/10/19

AC Electrical Characteristics Continued5

LIMITS

PARAMETER

SYMBOL

VCC

CONDITIONS

25°C

85°C

FULL RANGE

4

UNITS

Inputs A, B, R

10

10

10

Maximum Input

Capacitance

CIN

-

CX, RX

25

25

25

pF

TYPICAL

Power Dissipation

Capacitance Per

Multivibrator

6

CPD

-

TA = 25°C,

VCC = 5.0V

150

pF

6. Used to determine the no-load dynamic power consumption: PD = CPD VCC

2f + ICC VCC.

Timing Requirements5

LIMITS

PARAMETER

SYMBOL

VCC

CONDITIONS

25°C

85°C

FULL RANGE

5

UNITS

2.0V

50

65

65

4.5V

10

13

13

Minimum Recovery

Time, Reset Inactive to

A or B

(Figure 3)

trec

6.0V

tr = tf = 6ns

9

11

11

ns

2.0V

100

125

125

4.5V

20

25

25

Minimum Pulse Width,

Input A or B

(Figure 2)

tw

6.0V

tr = tf = 6ns

17

20

20

ns

2.0V

100

125

125

4.5V

20

25

25

Minimum Pulse Width,

R

(Figure 3)

tw

6.0V

tr = tf = 6ns

17

20

20

ns

2.0V

1000

1000

1000

4.5V

500

500

500

Maximum Input Rise

and Fall Times, R

(Figure 3)

tr, tf

6.0V

tr = tf = 6ns

400

400

400

ns

2.0V

4.5V

Maximum Input Rise

and Fall Times, A or B

(Figure 3)

tr, tf

6.0V

tr = tf = 6ns

No Limit

ns

When CX > 10nF and RX > 10K

the typical output pulse width value is defined by the formula:

Timing Requirements - Pulse width formula

Where:

tw = pulse width in ns

RX = external resistor in kΩ

CX = external capacitor in pF

VCC = 5V, tW = 0.45 x RX x CX