Chapter 3
Signal Connections
3-4
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Front Connector Signal Descriptions
SCXI-1120/D front connector signal descriptions are listed in Table 3-1.
The signals on the front connector are all analog with the exceptions of pins
A6, C6, and C8. The analog signals can be divided into two groups—the
analog input channels and the temperature sensor.
Table 3-1.
SCXI-1120/D Front Connector Signal Descriptions
Pin
Signal Name
Description
A2
CHSGND
Chassis Ground—Tied to the SCXI chassis.
C2
DTEMP
Direct Temperature Sensor—Connects the
temperature sensor to pin 18 of the rear signal
connector MCH7- when the terminal block is
configured for direct temperature connection
and jumper W41 is in position 3.
A4
+5 V
+5 VDC Source—Powers temperature sensor
on the terminal block. 0.2 mA of source not
protected.
C4
MTEMP
Multiplexed Temperature Sensor—Connects
temperature sensor to output multiplexer.
A6, C6, C8
RSVD
Reserved—Reserved for future use. Do not
connect any signals to these pins. TTL/CMOS
output. They are not protected.
A8, A10, C10, A16,
C16, A22, C22, A28,
C28
Not Connected
Do not connect any signals to these pins.
A12, A14, A18, A20,
A24, A26, A30, A32
CH7+ through CH0+
Positive Input Channels—Positive inputs to
channels 7 through 0, respectively.
C12, C14, C18, C20,
C24, C26, C30, C32
CH7– through CH0–
Negative Input Channels—Negative inputs to
channels 7 through 0, respectively.
