Chapter5 SignalConnections
©NationalInstruments Corporation 5-13 7344/7334Hardware User Manual
scanrate performan ce.Pro perly enabled, the scan rate is high enough
to support analogfeedback at the h ighest PID sample rate.
•Analog Reference—Forconvenience, 7.5 V (nominal) analog
reference voltageis made available. You can use this output as a low
currents upply to sensors that require a stable reference.
•Analog Input Ground—Tohelp keep digital noise out of the analog
input, a separate return connection is provided. Youshould use this
reference ground connection and not Digital Ground (digital I/O
reference) or AnalogOutput G roundas the reference for the analog
inputs.
Wiring Concerns
Forproper use of each A DC input channel, the analogsignal to be
measuredshould be connected to the channel input and its ground r eference
connected to the Analog Input Ground.
Note If an external reference voltageis used, it must n ot be connected to the analog
reference output, since this is an output signal only.You should, however, connect the
commonof the external reference to the Analog Input Ground pin for proper A/D reference
and improvedvoltage measurement.
Other Motion I/O Connections
The 7344/7334 controller provides other motion I/O connections as
follows:
•Host+5 V—Thisis the internal +5 Vsupply of the host computer. This
signalis typically used to detect when the host computer is powered
and to shut downexternal motion system components whe nthe host
computeris turned off or disconnected from the motion accessory.
Caution Thehost +5 V signal is limited to <100 mA and should no t beu sedto power any
externaldevices, except those intended in the host bus monitor circuits on the UMI and
driveproducts.