ADLINK cPCI-7300 - Manual (Page 22)

14
• Installation
2.7 Wiring and Termination
Transmission line effects and environment noise, particularly on clock and
control lines, can lead to incorrect data transfers if you do not take care when
running signal wires to and from the devices.
Take the following precautions to ensure a uniform transformation line and
minimize noise pickup:
1. Use twisted-pair wires to connect digital I/O signals to the device. Twist each
digital I/O signal with a GND line. In PCI-7300A, 50 signals are used as
GND.
2. Place a shield a round the wires connecting digital I/O signal to device.
3. Route signals to the devices carefully. Keep cabling away from noise
sources, such as video monitor.
For cPCI/PCI-7300A, it is important to terminate your cable properly to reduce
or eliminate signal reflections in the cable. The PCI-7300A support active
terminator on board, you can enable or disable the terminator by software
selection. This is a good way to include termination on the signal transmission.
Additional recommendations apply for all signal connection to your
cPCI/PCI-7300A are listed as follows:
1. Separate cPCI/PCI-7300A device signal lines from high-current or
high-voltage line. These lines are capable of inducing currents in or voltages
on the cPCI/PCI-7300A if they run in parallel paths at a close distance. To
reduce the magnetic coupling between lines, separate them by a
reasonable distance if they run in parallel, or run the lines at right angles to
each other.
2. Do not run signal lines through conducts that also contain power lines.
3. Protect signal lines from magnetic fields.