Brother PT-2500PC, Service Manual, Page: 60 / 79

III - 10
3.2.7 Thermal Head Control Circuit
Fig. 3.2-7 shows the thermal head control circuit. The print head integrates a heat
generator (consisting of 128 heating elements vertically aligned in 180 dpi) and a pair of
built-in driver ICs which are designed for 64-element control.
Synchronizing with the clock on P61, the CPU outputs serial print data containing 128-
dot frame (8 x 16 bit map) through P63 to the drivers.
If the CPU runs out of control, this circuit cuts off the strobe signal (P80) to the thermal
head after the specified time length by the CR time constant of C17
•
R46.
Fig. 3.2-8 shows the head drive timing scheme.
Fig. 3.2-7 Thermal Head Control Circuit
Fig. 3.2-8 Head Drive Timing Scheme