Service manual

54
ViewSonic Corporation Confidential - Do Not Copy VA503b-2_VA503m-2
9. Block Diagram
XTAL
14.318MHz
TOP245Y
OPP/OCP
LDO
3.3V-1.8V
Transformer
OZ9938G
Rectifier &
Filter Circuit
Panel Interface
TDA7496L
Keyboard
Lamp2
Keypad
Connector
VGA Input
VGA Connector
AC Line Filter
AC Socket
TFT LCD Panel 15"
MT150XN03 V0(Innolux)
Feedback
OVP
LTV817
Power
Transformer
Power
Lamp1
Audio In
AC Input 90V-240V
Phone
Jack
24C04
Open
Protection
Rectifier &
Filter Circuit
24C02
VA503b/m Block Diagram
Note: the parts in dashed line are for VA503m only.
Speaker
On/Off
Brightness
On/Off
Brightness
14V
3.3 V
AP2305GN
PMBT3906
Panel Enable
AP9971
1
2
12
3.3V
TSUM16AL
flash
Connector