Led Print Head - Kyocera Mita FS-C5016N - Color LED Printer Service Manual

Data to print is processed by the main controller PWB and transferred to the LED print head relay PWB in synchronization
with VIDEO signal through the engine controller PWB.VIDEO signal is sent from ASIC (U22) on the mail controller PWB to
ASIC (U551) on the LED print head relay PWB using LVDS method. LVDS stands for Low Voltage Differential Signaling
which uses 16 pairs of signal lines (32 in all).The main controller PWB converts VIDEO signal into a unique format using
LVDS depending on compensating data stored in a flash DIMM.
The LED print head has an LED print head memory PWB mounted. The PWB includes data for compensating the fluctua-
tion of luminosity of every LED chip. At power-up, the compensating data in EEPROM are cached in the flash DIMM on the
main controller PWB. In a subsequent power-up, the main controller PWB refers the flash DIMM to obtain the compensat-
ing data and the EEPROM is checked with its checksum only.
If the LED print head or the main controller PWB is replaced, checksum becomes error. The compensating data is trans-
ferred to the controller PWB again from the EEPROM. In case of failure with EEPROM on the LED print head memory
PWB or with compensating data, the printer displays service call 0951, 0952, 0953, or 0954 within approximately 30 sec-
onds.
STREQ1, STROBE1,
HSYNC1, STBCLK1
D110 to 119
D120 to 129
Drum unit
Drum unit
LED
memory
print
head
Drum
LED print heads
relay PWB
ASIC
(U551)
Drum unit
Drum unit
LED
print
head
PWB
Figure 2-1-19 LED print head block diagram
Engine
controller
PWB
LVDS
EEDATA
Serial
communication
(U8)
LVDS: Low Voltage Differential Signaling
FS-C5016N
Main
controller
PWB
LVDSN0 to 15
VIDEO
data
output
LVDSP0 to 15
ASIC
(U22)
SOUT
SIN
Serial
communication
Flash
DIMM
2-1-15