7

Test Circuits and Waveforms

FIGURE 1. OUTPUT PULSE CONTROL USING RESET INPUT

(R) PULSE FOR 123

FIGURE 2. OUTPUT PULSE CONTROL USING RESET INPUT

(R) FOR 423

FIGURE 4. TYPICAL OUTPUT PULSE WIDTH AS A FUNCTION

B = LOW

A = HIGH

Q

R

B

A

A

B

R

B = LOW

A = HIGH

Q

A

B

B

A

Q

(R = HIGH)

NOTE: Output pulse control using retrigger pulse for 123 and 423.

2

4

6

8

2

4

6

8

2

4

6

8

2

4

6

8

24 6 8

2

4 68

2

4 68

2

4 68

=

100k

Ω

=

10k

Ω

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

12

3

4

5

6

7

8

9

10

11

HCT

CD74HC123, CD74HCT123, CD74HC423, CD74HCT423