Oki OF5600, Service Manual

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Board Descriptions A - 30 OF 5300/5600 Serv Man, P/N 59278301
A3.2.9 M17 Circuit Diagram
1. Block diagram
The circuit diagram consists of connector CN2 that provides an interface between M17
board and LED print head.
Figure A3.2.12 shows the related signals and block diagram of LED print head.
2. Function
Data of 1664 LEDs on the LED print head is loaded into the shift registers by the HCLCK
(6.67 MHz) signal. After the 1664 bit (208mm) 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 IOGA
•
HDATA 0: Print data i.e., data to be printed
• HCLCK: Transfer clock for print data (6.67 MHz/10MHz)
• HLATCH: Latch signal for print data
• STRB1-N to STRB4-N : LED head strobe signals
Shift register
Latch
Strobe
CN2
8
6
9
10, 11, 12, 13
1, 2
3, 4
5, 14
+5 V
0 V
LED
1664 bits (208 mm)
LED print head
M17
HCLCK (6.67 MHz)
HDATA
HLATCH
STRB1-N to STRB4-N
0 VP
+5 V
0 V
IOGA
IC2
Related Signals and Block Diagram of LED Head (Figure A3.2.12)
Rev. 2