Seiko LTP F Series, Reference Manual

Page: 48 / 86

3-30
Table 3-14 Paper Detector Input/Output Conditions
Item Symbol Conditions Min. Std. Max.
Forward voltage V
F
I
F
=10 mA 1.0 V 1.2 V 1.6 V LED (input)
Reverse current I
R
V
R
=5 V
 
10
µ
A
Photo-
transistor
(output) Dark current I
CEO
I
F
=0 mA, V
CE
=10 V
 
200 nA
Photoelectric current I
C
I
F
=10 mA, V
CE
=5 V 150
µ
A

600
µ
A
Leak current I
LEAK
I
F
=10 mA, V
CE
=5 V
 
1
µ
A
Collector saturation
voltage V
CE
(sat) I
F
=10 mA, I
C
=5
µ
A
 
0.5V
Response time
(at rise) tr

5
µ
s

Transfer
characteristics
Response time
(at fall) tf
I
C
=1mA, V
CC
=5 V
R
L=
100
Ω

5
µ
s

3.7.2 Sample External Circuit
∗
The PS signal is high when there is no paper.
Figure 3-15 Sample External Circuit of the Paper Detector
PS
VPS
GND
Photo-interrrupter
To CPU port
V
dd
(5 V) V
dd
(5 V)
47 k
Ω
220
Ω
GND
LTP F Series
74HC04
0.1
µ
F