3-26
3.7 PAPER
DETECTOR
The printer has a built-in paper detector (reflection type photo interrupter) to detect whether paper is
present or not.
An external circuit should be designed so that it detects output from the paper detector and does not
activate the thermal head and motor when there is no paper. Doing not so may cause damage to the
thermal head or platen roller or shorten the longevity of the head significantly. If the motor is drived
when it is out-of-paper, a load is put on the reduction gear and the longevity of the gear may be
shortened.
3.7.1 General
Specifications
Table 3-11 Absolute Maximum Ratings of Detectors
(at 25
°
C)
Item
Symbol
Rating
Forward current
I
F
50 mA
Reverse voltage
V
R
5 V
LED (input)
Allowable current loss
P
70 mW
Collector-to-emitter
voltage
V
CEO
20 V
Emitter-to-collector
voltage
V
ECO
5 V
Collector current
I
C
20 mA
Phototransistor
(output)
Collector loss
P
C
70 mW
Operating temperature
T
opr
-20
°
C to + 80
°
C
Storage temperature
T
stg
-30
°
C to + 100
°
C