National Instruments USB-621 Series, User Manual

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Contents
© National Instruments Corporation vii NI USB-621x User Manual
Getting Started with AI Applications in Software.........................................................4-22
Connecting Analog Inp
u t Signals on USB-6210/6211/6212 Devices...........................4-23
Connecting Floating Signal So u rces ...............................................................4-25
What Are Floating Signal So u rces? ..................................................4-25
When to Use Differential Connections with
Floating Signal So u rces..................................................................4-25
When to Use Referenced Single-Ended Connections with
Floating Signal So u rces..................................................................4-25
When to Use Non-Referenced Single-Ended Connections with
Floating Signal So u rces..................................................................4-26
Using Differential Connections for Floating Signal So u rces............4-27
Using Non-Referenced Single-Ended Connections for
Floating Signal So u rces..................................................................4-30
Using Referenced Single-Ended Connections for
Floating Signal So u rces..................................................................4-31
Connecting Gro u nd-Referenced Signal So u rces .............................................4-31
What Are Gro u nd-Referenced Signal So u rces?................................4-31
When to Use Differential Connections with
Gro u nd-Referenced Signal So u rces ...............................................4-32
When to Use Non-Referenced Single-Ended Connections with
Gro u nd-Referenced Signal So u rces ...............................................4-32
When to Use Referenced Single-Ended Connections with
Gro u nd-Referenced Signal So u rces ...............................................4-33
Using Differential Connections for Gro u nd-Referenced
Signal So u rces ................................................................................4-34
Using Non-Referenced Single-Ended Connections for
Gro u nd-Referenced Signal So u rces ...............................................4-35
Connecting Analog Inp u t Signals on USB-6215/6216/6218 Devices...........................4-36
Taking Differential Meas u rements..................................................................4-36
Taking Referenced Single-Ended Meas u rements ...........................................4-37
Taking Non-Referenced Single-Ended Meas u rements ...................................4-38
Chapter 5
Analog Output
AO Range ......................................................................................................................5-2
Minimizing Glitches on the O
u tp u t Signal ....................................................................5-2
Analog O u tp u t Data Generation Methods .....................................................................5-2
Analog O u tp u t Digital Triggering .................................................................................5-4
Connecting Analog O u tp u t Signals ...............................................................................5-4
Analog O u tp u t Timing Signals ......................................................................................5-5
AO Start Trigger Signal...................................................................................5-5
Using a Digital So u rce ......................................................................5-5
Ro u ting AO Start Trigger to an O u tp u t Terminal.............................5-6