National Instruments USB-6008/6009 Manual De Usuario
© National Instruments Corporation
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USB-6008/6009 User Guide and Specifications
Figure 9. Connecting a Reference Single-Ended Voltage Signal
Digital Trigger
When an AI task is defined, you can configure PFI 0 as a digital trigger
input. When the digital trigger is enabled, the AI task waits for a rising edge
on PFI 0 before starting the acquisition. To use ai/Start Trigger with a
digital source, specify PFI 0 as the source and select rising edge.
input. When the digital trigger is enabled, the AI task waits for a rising edge
on PFI 0 before starting the acquisition. To use ai/Start Trigger with a
digital source, specify PFI 0 as the source and select rising edge.
Analog Output
The USB-6008/6009 has two independent AO channels that can generate
outputs from 0–5 V. All updates of AO lines are software-timed.
outputs from 0–5 V. All updates of AO lines are software-timed.
Analog Output Circuitry
Figure 10 illustrates the analog output circuitry for the USB-6008/6009.
Figure 10. Analog Output Circuitry
DACs
Digital-to-analog converts (DACs) convert digital codes to analog
voltages.
voltages.
AI
Voltage
Source
USB-6008/6009
GND
REF(+) REF(–)
12-Bit
DAC
Output
Buffer
50
Ω
AO
+5 V
GND