Circuit Diagram (6/13) - Oki OKIFAX4550 Maintenance Manual

3.6 46F Circuit Diagram (6/13)
1. Block diagram
46F-PCB circuit diagram (6/13) shown the consists of connector CN12 that provides an interface
between 46F board and LED print head.
Figure A.11 (1/2) 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 (4MHz
or 6.7 MHz) signal. After the 1664 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 IOGA4
• HDATA 0
• HCLCK
• HLATCH
• STRB1-N to STRB4-N : LED head strobe signals
3. Signal timing
Figure A.11 (2/2) shows the timing chart of LED print head.
IC2
HCLCK (1.0 MHz)
HDATA 0
HLATCH
IOGA4
STRB1-N to STRB4-N
Figure A.11 (1/2) Related Signals and Block Diagram of LED Head
41309401TH Rev.4
: Print data i.e., data to be printed
: Transfer clock for print data (4.0 MHz or 6.7 MHz)
: Latch signal for print data
46F
CN12
8
6
9
10,11,12,13
1,2
0VP
3,4
+5V
5,14
0V
LED print head
Shift register
Latch
Strobe
+5V
0V
LED
1664 bits
(208 mm)
316 /