6

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Single-Channel: 6N138, 6N139 Dual-Channel: HCPL-2730, HCPL-2731 Rev. 1.0.2

Current Limiting Resistor Calculations

Where:

Output Transistor

Resistor R2

3

4

2

1

6

5

7

8

2

R

1

R

IN

OUT

DD2

V

IN

4

3

2

5

6

7

OUT

1

8

DD2

V

Fig. 2 Non-Inverting Logic Interface

Fig. 3 Inverting Logic Interface

INPUT

R1 (V)

OUTPUT

CMOS

@ 5 V

CMOS

@ 10 V

74XX

74LXX

74SXX

74LSXX

74HXX

R2 (V)

R2 (V)

R2 (V)

R2 (V)

R2 (V)

R2 (V)

R2 (V)

CMOS

@ 5 V

NON-INV. 2000

1000

2200

750

1000

1000

1000

560

INV.

510

CMOS

@ 10 V

NON-INV. 5100

INV.

4700

74XX

NON-INV. 2200

INV.

180

74LXX

NON-INV. 1800

INV.

100

74SXX

NON-INV. 2000

INV.

360

74LSXX NON-INV. 2000

INV.

180

74HXX

NON-INV. 2000

INV.

180

Fig. 1 Resistor Values for Logic Interface