Seiko Instruments LTP F Series User Manual

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 the output from the paper detector and does
not activate the thermal head when there is no paper. Doing not so may cause damage to the thermal
head or platen roller or shorten the life of the thermal head significantly.

Table 3-13  Absolute Maximum Ratings of the Paper Detector (at 25

°C)

Forward current

I

F

50 mA

Reverse voltage

V

R

5 V

LED (input)

Allowable current

P

75 mW

Collector-to-emitter voltage

V

CEO

20 V

Emitter-to-collector voltage

V

ECO

5 V

Collector current

I

C

20 mA

Photoransistor
(output)

Collector loss

P

C

70 mW

Operating temperature

T

opr

-20  to +80

°C

Storage temperature

T

stg

-30  to +100

°C