3. External Connection
AD12-8(PM)
41
Analog Input Signal Connection
This section describes examples of connecting analog input signals using flat cable or shield cable.
The following is an example of how to connect using a cable such as a separately purchased flat cable
(PCA37P).
Connect separate lines for both the signal source and ground for each analog input channel in CN1.
Analog Input 0..15
Analog Ground
CARD
Connector
Cable
Signal Source
Figure 3.4. Single-ended Input Connection (Flat Cable)
The following figure shows an example of shield cable connection. Use shielded cable if the distance
between the signal source and PC card is long or if you want to provide better protection from noise.
For each analog input channel on CN1, connect the core wire to the signal line and connect the shielding
to ground.
Analog Ground
Shield cable
Analog Input 0..15
CARD
Connector
Signal Source
Figure 3.5. Single-ended Input Connection (Shield Cable)
CAUTION
-
If the signal source contains over 1MHz signals, the signal may effect the cross-talk noise between
channels.
-
If the PC card and the signal source receive noise or the distance between the PC card and the
signal source is too long, data may not be input properly.
-
An input analog signal should not exceed the maximum input voltage (relate to the PC card analog
ground). If it exceeds the maximum voltage, the PC card may be damaged.
-
Connect all the unused analog input channels to analog ground.
-
The input impedance of the input terminals is 20k
Ω
or higher. Use a signal source with a suitably
low output impedance.
