Panasonic KX-FP80C, Руководство по обслуживанию

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2. Circuit Operation
Refer to the block diagram and the timing chart on the following
page.
There are 9 driver ICs aligned horizontally on the thermal head and
each one of these ICs can drive 192 heat-emitting registers. This
means that one line is at a density of 192×9=1728 dots=(8 dots/
mm).
White/Black (white=0, black=1) data in one line increment is
synchronized at IC501 pin 115 (THCLK), and sent from IC501 pin
114 (THDAT) to the shift register of the ICs. The shift registers of
the 9 ICs are connected in series, and upon the shift of the 1728
dot increment, the shift register becomes filled with data, and a
latch pulse is emitted to each IC from IC501 pin 118 (THLAT).
With this latch pulse, all the contents of the shift registers are
latched to the latch registers. Thereafter, through the addition of
strobes from the IC501 pins (105, 106), only the dot location of
black (=1) among latched data activates the driver, and the current
passes to heat the emitting body to cause heat emission.
Here, the two line strobes, STB1 and STB2, impress at intervals of
9.216 msec, as required for one-line printout.
The sequence is shown on the next page. [Moreover, for the strobe
width, the thermistor value inside the thermal head is detected
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