rtd cpuModule CMC6686GX, User Manual

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Power Supply Protection
The cpuModule has protection circuitry which helps prevent damage due to problems with the +5V
supply, such as:
• Reversed polarity
• Overvoltage
• Overcurrent
The circuitry includes a user-replaceable fuse, which is located near the PC/104 bus connector. This
fuse is a:
• 3 amp Nano fuse
• Littelfuse part number R451 003 or 429003WR
NOTES! -5 VDC, +12 VDC and -12 VDC voltages are not used by the module,
but are connected to the PC/104 bus connectorsP4 or CN1 and P7 or
CN2
The 3.3 volt pins on power connector P9 or CN3 are used to monitor
the onboard 3.3 voltage regulator. In effect, these pins (10 and 12)
become outputs. Don’t use these pins as a source of 3.3 volts to
another board and don’t connect these pins to a 3.3 volt power supply.
The CPU V+ pin (pin 11 of P9or CN3)is used to monitor the onboard
CPU regulator which is 2.5 volts. Don’t use this as source of 2.5 volts
and don’t connect this pin to a 2.5 volt power supply.
Pins 10 and 12 on P9 or CN3 are floating by default factory setting.
These pins are not for monitoring or power. If monitoring is needed at
these pins, please contact us for details.