©
National Instruments Corporation
3
BNC-9920 Operating Instructions and Specifications
Figure 1.
BNC-9920 Front Panel
1
RES/BNC Switch (AI 3)
2
Resistor Measurement Screw
Terminals
3
Thermocouple Input Connector
4
Temperature Reference
5
BNC/Temp. Ref. Switch (AI 0)
6
BNC/Thermocouple Switch (AI 1)
7
Analog Input BNC Connectors
8
FS/GS Switches
9
Analog Output BNC Connector
10 Frequency Range Selection Switch
11 Sine/Triangle BNC Connector
12 TTL Square Wave BNC Connector
13 Sine/Triangle Waveform Switch
14 Frequency Adjust Knob
15 Amplitude Adjust Knob
16 Digital I/O Screw Terminals
(DIO 0–7)
17 Digital I/O LEDs
18 User-Defined Screw Terminals
19 User-Defined BNC Connectors
20 Digital I/O Screw Terminals
(DIO 9–20)
21 Quadrature Encoder Screw
Terminals
22 Quadrature Encoder Knob
23 Digital I/O BNC Connector (DIO 8)
24 Power Indicator LED
E
L
R
T
T
S
N
I
NA
M
U
N
O
I
A
S
T
N
_
+
Floating
Source (FS)
_ +
Ground Ref.
Source (GS)
AO
ANALOG OUTPUTS
ANALOG INPUTS
DIGITAL I/O
FUNCTION GENERATOR
Frequency Selection
Amplitude Adjust
Sine / Triangle
TTL Square Wave
Frequency Adjust
GS
FS
GS
FS
GS
FS
GS
FS
GS
FS
GS
FS
GS
FS
GS
FS
AI 0
AI 1
USER 1
USER 2
DIO 7
DIO 6
DIO 5
DIO 4
DIO 3
DIO 2
DIO 1
DIO 0
D GND
AI 2
BNC
RES+
AI GND
AI SENSE
RES-
1
2
3
4
Temp.
Ref.
0.1-10 kHz
LO
HI
LO
HI
1-100 kHz
13-1000 kHz
Thermo
couple
BNC
RE
S
AI 3
BNC
AI 3
AI 4
AI 5
AI 6
AI 7
AO 0
AO 1
USER-DEFINED
SIGNALS*
*For BNC connections,
wire any Digital I/O
screw terminals here.
PWR
BNC-9920
DIGITAL I/O
DIO 8
96 Pulses / Rev
Quadrature
Encoder
DIO 9
DIO 10
DIO 11
DIO 12
DIO 13
DIO 14
DIO 15
DIO 16
DIO 17
DIO 18
DIO 19
DIO 20
+5 V
PULSES
UP / DN
D GND
1.
2.
3.
4
.
!
10
16
17
1
5
7
9
8
4
6
2
12
14
1
3
11
15
19
20
2
3
22
24
21
3
1
8