Advantech SOM-ETX Design Guide
KBDAT
MSCLK
MSDAT
Keyboard Connector
Mini-dim 6P
SOM-ETX
KBDAT
VCC
KBCLK
GND
Mouse Connector
Mini-dim 6P
KBCLK
VCC
VCC
KBDAT
VCC
KBCLK
GND
Chassis Ground
Fuse 1A
Fuse 1A
Ferrite Bead
Ferrite Bead
Digital Ground
1A Trace Wide
1A Trace Wide
Figure 5-36 Practical KB/MS circuit
5.12 TV-Out
5.11.4 EMI Consideration
To avoid EMI, the ground plane of keyboard/mouse connector, and other digital
ground planes, power planes should be separated with an isolation moat, which is
recommended to be at least 40 mils. These planes should be connected via screw
holes to assure the completeness of ground plane.
More EMI consideration, please refer to 5.10.3.1.
5.11.4.1 ESD Protection
Please refer to section 5.10.3.2.
TV out display (TV DAC) interface consists of 4 output , TVSYNC ,Y,C,COMP which
can be used in different combinations to support S-video or composite video.
5.12.1 Signal Description
Table 5.23 TV signals description
Pin Signal
C49 TVSYNC
O
Composite sync for SCART/PAL TVs that use the Euro AV connector.
It is fed to the .video in. pin of this connector to provide a signal that
the TV can overlay RGB data onto. This pin may also be used as a
general I/O pin for controlling the video, or for other internal timing
signals including HYSNC, VSYNC etc.
C48 Y
O
DAC Output: outputs either Y (Luminance) for S-Video, or Red for
RGB Video (SCART).
C50 C
O
DAC Output: outputs either C (Color/Chrominance) for S-Video, or
Green for RGB Video.
C47
COMP
O
DAC Output: outputs either Composite Video, or Blue for RGB Video.
I/O Description
102
Chapter 5 Carrier Board Design Guidelines