Digital Trigger; Analog Output - National Instruments USB-6008 User Manual

Figure 11. Connecting a Referenced Single-Ended Voltage Signal
AI
Voltage
NI USB-6008/6009
Source
GND
When no signals are connected to the analog input terminal, the internal resistor divider may
cause the terminal to float to approximately 1.4 V when the analog input terminal is
configured as RSE. This behavior is normal and does not affect the measurement when a
signal is connected.

Digital Trigger

You can configure PFI 0 as a digital trigger input for analog input tasks. Refer to the Using
PFI 0 as a Digital Trigger section for more information.

Analog Output

The NI USB-6008/6009 has two independent analog output channels that can generate outputs
from 0 V to 5 V. All updates of analog output channels are software-timed. GND is the
ground-reference signal for the analog output channels.
The following figure shows the circuitry of one analog output channel on the
NI USB-6008/6009.
Figure 12. Circuitry of One Analog Output Channel
+5 V
REF(+) REF(–)
50 Ω
AO
12-Bit
DAC
GND
The main block featured in the NI USB-6008/6009 analog output circuitry is the
digital-to-analog converter (DAC), which converts digital codes to analog voltages. There is
one DAC for each analog output line.
NI USB-6008/6009 User Guide | © National Instruments | 17