©2005 Fairchild Semiconductor Corporation www.fairchildsemi.com
MCT2M, MCT2EM, MCT210M, MCT271M Rev. 1.0.2 5
MCT2M, MCT2EM, MCT210M, MCT271M — Phototransistor Optocouplers
Typical Performance Curves
Fig. 2 Normalized CTR vs. Forward Current
I
F
– FORWARD CURRENT (mA)
02468101214161820
NORMALIZED CTR
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
V
CE
= 5.0V
T
A
= 25°C
Normalized to
I
F
= 10mA
Fig. 3 Normalized CTR vs. Ambient Temperature
T
A
– AMBIENT TEMPERATURE (°C)
-60 -40 -20 0 20 40 60 80 100
NORMALIZED CTR
0.2
0.4
0.6
0.8
1.0
1.2
1.4
I
F
= 5mA
I
F
= 10mA
I
F
= 20mA
Normalized to
I
F
= 10mA
T
A
= 25°C
I
F
– LED FORWARD CURRENT (mA)
V
F
– FORWARD VOLTAGE (V)
Fig. 1 LED Forward Voltage vs. Forward Current
110100
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
T
A
= 25°C
T
A
= 55°C
T
A
= 100°C
Fig. 5 CTR vs. RBE (Saturated)
R
BE
– BASE RESISTANCE (kΩ)
NORMALIZED CTR ( CTR
RBE
/ CTR
RBE(OPEN)
)
10 100 1000
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
I
F
= 20mA
I
F
= 10mA
I
F
= 5mA
V
CE
= 0.3V
Fig. 4 CTR vs. RBE (Unsaturated)
R
BE
– BASE RESISTANCE (kΩ)
NORMALIZED CTR ( CTR
RBE
/ CTR
RBE(OPEN)
)
10 100 1000
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
V
CE
= 5.0V
I
F
= 20mA
I
F
= 10mA
I
F
= 5mA
0.01 0.1 1 10
0.001
0.01
0.1
1
10
100
I
F
= 5mA
I
F
= 20mA
I
F
= 10mA
Fig. 6 Collector-Emitter Saturation Voltage vs Collector Current
I
C
– COLLECTOR CURRENT (mA)
V
CE (SAT)
– COLLECTOR-EMITTER SATURATION VOLTAGE (V)
I
F
= 2.5mA
T
A
= 25°
C