Circuit Description Of Operation Panel Pwb - Sharp FO-DC600 Service Manual

FO-DC600U

[5] Circuit description of operation panel PWB

1. Operational description
1) Operation panel PWB
The operation panel PWB includes the ten key scan circuit and the LED
lighting circuit.The LS145 is controlled through LD0~LD3 (4 bits) and
ten key detection is performed. The HC174 is controlled through
LD0~LD5 (6 bits) to provide LED lighting information.
2) LCD (LM046QB1H01)
a. Scope of application
This specification applies to a positive diffusion type monochrome
dot matrix LCD module LM046QB1H01.
b. Structure and external shape
Structure: 320 x 240 monographic display module
This dot matrix LCD module consists of an LCD panel, a print PWB
mounting electrical parts, a TCP electrically connecting these units
and bezels fixing them mechanically.
2. Block diagram
PLTSW
SEN[7:0]
LD[7:0]
LEDEN1
LEDEN2
TH1
TH2
YD
LP
XCK
M
DISP
D[3:0]
PAGE PLATE SW
KEY MATRIX(10 x 8)
LD[3:0]
LS145
LD[5:0]
HC174
LD[5:0]
HC174
LCD RELAY PWB
Bezel
Fig. 10 Module construction plan
LED PWB
+5V
+5V
RT1
t
Fig. 11
5 – 18
LCD PANEL
TCP
(hard coating)
LCD
(320 x 240 DOTS LCD)
PWB