Sony UP-D2600S Service Manual page 111

Head Control Block
The head control block proccess the parallel print data for each line from the IF-787 or IF-788 board and
sends it to the thermal head for printing.
The head control block is constituted by the following five sections.
. γ ROM that γ collects the parallel print data from the IF-787 or IF-788 board.
. Image processing IC(Picture Quality Control IC) that performs pattern recognition interpolation, edge
emphasis, and heat accumulation correction.
. Head driving IC that PWM-converts parallel data and sends print data to the thermal head.
. Line number correction IC (Voltage drop control IC) that corrects voltage drop by common resistor of
the thermal head.
. Head voltage correction circuit
The print data is received from the IF-787 or IF-788 board as parallel data for γ correction. Each signal
processing is added by PQC IC. After that, PWM modulation is performed by head driving IC and the
print data is sent to the thermal head.
γ correction block
8
DATA
PRINT DATA
2
DMA CONTROL
UP-D2600/V1(E)
Image processing block
8
Picture
Quality
Control
IC
8
PRINT DATA
5
DMA CONTROL
3
CONTROL
9
ADDRESS
8
DATA
Line number correction processing block
Thermal head driving block
16
Thermal
PRINT DATA
2
Head
Drive
LATCH
DCX
IC
Voltage
Drop
Control
STROBE
IC
4-17