Chapter 7. Circuit Description - Sharp ER-A750 Service Manual

CHAPTER 7. CIRCUIT DESCRIPTION

1. Hardware block diagram
Drawer x 2
DRIVER +24V
DRIVER +24V
IR
USART
RS232 x 2
DRIVER/
RECEIVER
SRN
VRAM
(SRAM
32K)
LCD
320 x 240 dots
CPU
H8/510
MPCA7
&
OPC1
LCD CONTROLLER
CKDC7
BRIGHTNESS
CONTROL KNOB
INVERTOR
LIQUID-CRYSTAL BIAS
POWER SUPPLY
CONTRAST
ADJUSTMENT
/KNOB
7 – 1
FLASH
(ROM)
1MB
PSEUDO
SRAM
512KB
SW
CUSTOMER DISP.
POWER SUPPLY FOR
VACUUM FLUORESCENT
TUBE
+5V
-24V
POWER SUPPLY
VCC
EXT.SLOT
(80pin x 2)
RAMCN
(50pin)
KEY
+24V