3. External Connection
32
ADA16-32/2(PCI)F
Analog Input Signal Connection
The procedure for connecting analog signals depends on whether the analog input signals are
single-ended or differential. The sections below describe how to connect the signals using flat cable
and shielded cable.
Single-ended Input
The following figure shows an example of flat cable connection.
Connect separate signal and ground wires for each analog input channel on CN1.
Analog Input 0..31
Analog Ground
BOARD
CN1
Cable
Signal Source
Figure 3.3. 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 board 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..31
BOARD
CN1
Signal Source
Figure 3.4. 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 board and the signal source receive noise or the distance between the board 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 board analog
ground). If it exceeds the maximum voltage, the board may be damaged.
-
Connect all the unused analog input channels to analog ground.
-
In the channel switching, the multiplexer does the electrical charge and discharge on the internal
capacitor according to the signal voltage. Therefore, the voltage from the previous switching state
may go into the next channel. It might cause the error of the signal source action. If this occurs,
insert a high-speed amplifier as a buffer between the signal source and the analog input pin to
reduce the fluctuation.
-
An input pin may fail to obtain input data normally when the signal source connected to the pin has
high impedance. If this is the case, change the signal source to one with lower output impedance
or insert a high-speed amplifier buffer between the signal source and the analog input pin to reduce
the effect.
Summary of Contents for ADA16-32/2(PCI)F
Page 7: ...vi ADA16 32 2 PCI F ...
Page 33: ...2 Setup 26 ADA16 32 2 PCI F ...
Page 45: ...3 External Connection 38 ADA16 32 2 PCI F ...
Page 99: ...5 About Software 92 ADA16 32 2 PCI F ...
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