3.7PAPER 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 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.

3.7.1General Specifications

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

 

 

Item

Symbol

Maximum Rating

 

 

 

 

 

LED (input)

 

Forward current

IF

50 mA

 

 

 

 

 

 

 

Reverse voltage

VR

5 V

 

 

Allowable current

P

75 mW

 

 

 

 

 

Photoransistor

 

Collector-to-emitter voltage

VCEO

20 V

(output)

 

 

 

 

 

Emitter-to-collector voltage

VECO

5 V

 

 

 

 

 

 

 

 

 

Collector current

IC

20 mA

 

 

Collector loss

PC

70 mW

Operating temperature

 

Topr

-20 to +80°C

 

 

 

 

Storage temperature

 

Tstg

-30 to +100°C

 

 

 

 

 

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