Chapter 11
Triggering
Triggering with an Analog Source
Some X Series devices can generate a trigger on an analog signal. To find your device triggering
options, refer to the device specifications.
Figure 11-2 shows the analog trigger circuit on MIO X Series devices.
Figure 11-2. MIO X Series Device Analog Trigger Circuit
Analog
Input
Channels
Figure 11-3 shows the analog trigger circuit on Simultaneous MIO X Series devices.
Figure 11-3. Simultaneous MIO X Series Device Analog Trigger Circuitry
+
NI-PGIA
–
Analog
Input
Channels
+
NI-PGIA
–
You must specify a source and an analog trigger type. The source can be either an APFI <0,1>
terminal or an analog input channel.
APFI <0,1> Terminals
When you use either APFI <0,1> terminal as an analog trigger, you should drive the terminal
with a low impedance signal source (less than 1 kΩ source impedance). If APFI <0,1> are left
unconnected, they are susceptible to crosstalk from adjacent terminals, which can cause false
triggering. Note that the APFI <0,1> terminals can also be used for other functions such as the
11-2 | ni.com
+
PGIA
–
Mux
APFI <0..1>
ADC
Mux
ADC
APFI <0..1>
ADC
Analog Comparison
Analog
Event
Trigger
(Analog Trigger
Detection
Circuitry Output)
Analog Comparison
Analog
Event
Trigger
(Analog Trigger
Detection
Circuitry Output)
AI Circuitry
AO Circuitry
DIO Circuitry
Counter Circuitry
AI Circuitry
AO Circuitry
DIO Circuitry
Counter Circuitry