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Chapter 2
Connecting Signals
2-2
ni.com
Caution
The PFI 0/CAL SMB connector is for low-voltage timing and calibration signals
only
. Voltages greater than ±15 V can damage the device.
If you are building a 25-pin D-SUB connector for your application, make sure you use a
connector and wires that are safety rated for the voltage and category of the signals in your
application.
Table 2-1.
NI PXI-4224 25-Pin D-SUB Terminal Pin Assignments
Front Connector
Diagram
Pin Number
Signal Names
Pin Number
Signal Names
*
NC—No Connection
14
AI 0 –
1
AI 0 +
15
AI 1 –
2
AI 1 +
16
AI 2 –
3
AI 2 +
17
AI 3 –
4
AI 3 +
18
AI 4 –
5
AI 4 +
19
AI 5 –
6
AI 5 +
20
AI 6 –
7
AI 6 +
21
AI 7 –
8
AI 7 +
22
No Pin
9
No Pin
23
NC
*
10
D GND
24
SPI CLK
11
MISO
25
SELECT
12
MOSI
N/A
N/A
13
+5 V
14
15
16
17
18
19
20
21
22
23
24
25
123456789
1
0
1
1
1
2
1
3