19
Figure 9. Forward Voltage and Current
Characteristics.
Figure 10. Normalized Transmitter Output vs.
Forward Current.
Figure 11. Recommended Drive Circuit.
Figure 12. Test Circuit for Measuring tr, tf.
100
80
60
40
20
10
1.2
1.4
1.6
1.8
2.0
2.2
V
I - FORWARD VOLTAGE - V
I F
-
F
O
R
W
AR
D
C
U
RR
E
N
T
-
m
A
+85 °C
+25 °C
-40 °C
P(I
F
)–
P(60
mA)
–
RELATIVE
POWER
RATIO
0
2.0
0.8
0
IF – FORWARD CURRENT – mA
20
40
80
1.6
0.4
1.2
60
100
1.8
1.4
1.0
0.6
0.2
10
30
50
70
90
P(I
F
)–
P(60
mA)
–
RELATIVE
POWER
RATIO
–
dB
-7.0
-5.0
-4.0
-3.0
-2.0
-1.0
0
0.8
1.0
1.4
2.0
3.0
HFBR-14x2/x4
+5 V
R
y
R
X1
C
74F3037
7
8
5
R
X4
74F3037
R
X3
R
X2
74F3037
1
2
3
4, 5
+
4.7 F
15
14
74F3037
16
12, 13
0.1 F
10
11
9
HP8082A
PULSE
GENERATOR
SILICON
AVALANCHE
PHOTODIODE
50
TEST
HEAD
HIGH SPEED
OSCILLOSCOPE
50
LOAD
RESISTOR