8/10/04
Page 7 of 17
© 2004 Fairchild Semiconductor Corporation
LVTTL/LVCMOS COMPATIBLE LOW INPUT
CURRENT HIGH GAIN SPLIT DARLINGTON
OPTOCOUPLERS
SINGLE CHANNEL: FOD070L FOD270L
DUAL CHANNEL: FOD073L
TYPICAL PERFORMANCE CURVES
Fig. 13 Propagation Delay vs.
Ambient Temperature (FOD070L, FOD270L)
Fig. 14 Propagation Delay To Logic Low vs Pulse Period
(FOD073L, FOD070L, FOD270L)
T
A
- Ambient Temperature (°C) T - Pulse Period (ms)
-40 0.01 0.1 1 10-20 0 20 40 60 80 100
t
PHL
- Propagation Delay to Logic Low (
µs)
t
PLH
- Propagation Delay to Logic High (
µs)
t
PLH
t
PLH
t
PLH
t
PHL
t
PHL
t
PHL
0
8
6
4
2
10
12
14
t
PHL
- Propagation Delay to Logic Low (
µs)
1
10
100
0
80
60
40
20
100
120
140
Fig. 15 Propagation Delay vs.
Input Forward Current (FOD270L only)
Fig. 16 Propagation Delay vs.
Input Forward Current (FOD073L only)
I
F
- Input Forward Current (mA) I
F
- Input Forward Current (mA)
012345 678910
t
PHL
- Propagation Delay to Logic Low (
µs)
t
PLH
- Propagation Delay to Logic High (
µs)
0
2
1
3
4
5
42
50
48
46
44
52
012345 678910
t
PHL
- Propagation Delay to Logic Low (
µs)
t
PLH
- Propagation Delay to Logic High (
µs)
0
4
2
6
8
12
10
16
24
22
20
18
26
28
V
CC
= 3.3V
IF = 0.5mA
R
L
= 4.7kΩ
1/f = 200µs
Duty Cycle = 10%
T
A
= 25°C
V
CC
= 3.3V
I = 0.5mA
R
L
= 4.7kΩ
Duty Cycle = 50µs
FOD070L,
FOD270L
FOD073L
T
A
= 25°C
V
CC
= 3.3V
R
L
= 4.7kΩ
1/f = 100µs
Duty Cycle = 10%
T
A
= 25°C
V
CC
= 3.3V
R
L
= 4.7kΩ
1/f = 100µs
Duty Cycle = 10%
