Star Micronics TSP400 technical manual Theory Of Operation, 6 Timing Chart

THEORY OF OPERATION

CLOCK

SI

LATCH

STROBE1

STROBE2

STROBE3

STROBE4

STROBE5

COMMON

t

24V

Fig.2-6 Timing Chart

2-2-3. Head current control

Heat buildup in the head during operation can cause print quality to degrade. To maintain uniform quality, the printer varies the energizing time (time that STROBE remains LOW) in accordance with the head temperature.

The thermal head’s surface temperature is calculated based on the resistance value of an attached thermistor. Energizing time is reduced at higher temperatures, as indicated in the figure 2-6.

STROBE1, STROBE2, STROBE3

STROBE4, STROBE5,

EnergizingTime￿	600
	(tμsec)
	500
	400
Head	300

t

t

10 20 30 40 50

Thermistor Temp. (°C)

Fig. 2-7 Head Energizing Control

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