LOW INPUT CURRENT
HIGH GAIN SPLIT
DARLINGTON OPTOCOUPLERS
SINGLE-CHANNEL
6N138
6N139
DUAL-CHANNEL
HCPL-2730
HCPL-2731
ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise specified)
Current Limiting Resistor Calculations
R1 (Non-Invert) = VDD1 - VDF - VOL1
IF
R1 (Invert) = VDD1 - VOH1 - VDF
IF
R2 = VDD2 - = VOLX (@ IL - I2)
IL
Where:
VDD1 - Input Supply Voltage
VDD2 - Output Supply Voltage
VDF - Diode Forward Voltage
VOL1 - Logic “0” Voltage of Driver
VOH1 - Logic “1” Voltage of Driver
IF - Diode Forward Current
VOLX - Saturation Voltage of
Output Transistor
IL - Load Current Through
Resistor R2
I2 - Input Current of Output Gate
INPUT
R1 ($)
CMOS NON-INV. 2000
@5V
INV.
510
CMOS NON-INV. 5100
@ 10 V INV. 4700
NON-INV. 2200
74XX
INV.
180
NON-INV. 1800
74LXX
INV.
100
NON-INV. 2000
74SXX
INV.
360
NON-INV. 2000
74LSXX INV.
180
NON-INV. 2000
74HXX
INV.
180
OUTPUT
CMOS CMOS
@ 5 V @ 10 V 74XX 74LXX 74SXX 74LSXX 74HXX
R2 ($) R2 ($) R2 ($) R2 ($) R2 ($) R2 ($) R2 ($)
1000 2200 750 1000 1000 1000 560
Fig. 1 Resistor Values for Logic Interface
VDD1
VDD2
VDD2
1
2
3
IN
R1
4
8
7
R2
6
5
1
IN
2
OUT
3
R1
4
8
7
R2
6
OUT
5
Fig. 2 Non-Inverting Logic Interface
Fig. 3 Inverting Logic Interface
12/27/99 200023A