R46 Circuit Diagram (7/15) - Oki OKIFAX4550 Maintenance Manual

4.5

R46 Circuit Diagram (7/15)

1. Block diagram
R46-PCB circuit diagram (7/15) shown the consists of connector CN12 that provides an interface
between R46 board and LED print head.
Figure A.23 (1/2) shows the related signals and block diagram of LED print head.
2. Function
Data of 4992 LEDs on the LED print head is loaded into the shift registers by the HCLCK signal.
After the 4992 bit (208 mm) data is loaded in the shift registers, it is then loaded in the latch circuit
by the HLATCH signal. The turning -on and off of the LEDs are controlled by STRB1-N to STRB4-
N signals.
LED head interface signals output from IC2 (IOGA6)
• HDD0~3
• HDCLK
• HDDLD
• HDSTB1~4
3. Signal timing
Figure A.23 (2/2) shows the timing chart of LED print head.
IC2
IOGA6
Figure A.23 Related Signals and Block Diagram of LED Head
41309401TH Rev.4
: Print data i.e., data to be printed
: Transfer clock for print data
: Latch signal for print data
: LED head strobe signals
R46
CN14
HDCLK
2
HDD0~3 7,8,4,5
10
HDDLD
HDSTB1~4
11,12,13,14
6
0VP
9
+5V
1,3
0V
CN12
1~6
+5V
7~12
0V
LED print head
Shift register
Latch
Strobe
+5V
0V
LED
4992 bits
(208 mm)
335 /