User Manual

7-1. System Designing
Prevention of EM noise problem
Some transformers or coils in the po er nit generates EM noise
Some
transformers
or
coils
in
the
po
w
er
u
nit
generates
EM
noise
.
To
prevent
this
To
prevent
this
• Use transformers or coils that won’t allow magnetic flux leakage.
• Place them underneath the shield or in a distance as much as possible from the
sensor board.
• Position them so that EM noise flux did not across the senso
r
board.
EM noise source
•
Inverter
of
LCD
back
light
•
Inverter
of
LCD
back
light
• DC to DC converter in power circuit
18 • 30.10.2007 • Wacom Confidential