Theory of Operation Chapter 4
SCXI-1122 User Manual 4-2 © National Instruments Corporation
IEX+
IEX-
VEX+
VEX/2
VEX-
Current
Source
Voltage
Source
Configuration Register
LPF-Sel
Amplifier Input
Selector Control
Gain
Status Register
Digital Control
&
Interface
Rear Signal Connector
SCXIbus Connector
+1
AB0 Switch
AB0+ AB0-
MCH0+
MCH0-
AB0 Control
Attenuator
Calibration EEPROM
TEMP+
TEMP-
RSVD
CH0
CH7
CH8
CH15
+
-
+
-
+
-
+
-
IEX+ IEX-
VEX+
R
LPF
and
Protection
Temp+
Auto
Zero
Protection
Temp
+
MIEX
Mux
Counter
8 Input Relays
8 InputT/Output
Relays
Counter
Control
Amplifier Input Selection Control
LPF Gain
Gain
LPF
LPF-Sel
Gain
Gain
LPF
and
Output
Mux
LPF-Sel & Output Control
100:1
Attenuator
Amplifier Input
Selector
shunt
SENSE+
SENSE-