Measurement Computing USB-1608GX-2AO-OEM - Manual (Page 12)

USB-1608GX-2AO-OEM User's Guide Functional Details
12
Single-ended mode pinout
Pin Signal Name Description Pin Signal Name Description
1 CH0 Channel 0 29 CH15 Channel 15
2 CH8 Channel 8 30 CH7 Channel 7
3 AGND Analog ground 31 AGND Analog ground
4 CH1 Channel 1 32 CH14 Channel 14
5 CH9 Channel 9 33 CH6 Channel 6
6 AGND Analog ground 34 AGND Analog ground
7 CH2 Channel 2 35 CH13 Channel 13
8 CH10 Channel 10 36 CH5 Channel 5
9 AGND Analog ground 37 AGND Analog ground
10 CH3 Channel 3 38 CH12 Channel 12
11 CH11 Channel 11 39 CH4 Channel 4
12 AGND Analog ground 40 AGND Analog ground
13 AOUT0 Analog output 0 41 AGND Analog ground
14 AGND Analog ground 42 AGND Analog ground
15 AOUT1 Analog output 1 43 +5V +5V output
16 AGND Analog ground 44 AGND Analog ground
17 NC No connection 45 NC No connection
18 GND Digital ground 46 GND Digital ground
19 DIO0 Digital input/output 0 47 AICKI AI clock input
20 DIO1 Digital input/output 1 48 AICKO AI clock output
21 DIO2 Digital input/output 2 49 AOCKI AO clock input
22 DIO3 Digital input/output 3 50 AOCKO AO clock output
23 DIO4 Digital input/output 4 51 TRIG Trigger input
24 DIO5 Digital input/output 5 52 GND Digital ground
25 DIO6 Digital input/output 6 53 CTR1 Counter 1
26 DIO7 Digital input/output 7 54 CTR0 Counter 0
27 GND Digital ground 55 TMR Timer output
28 GND Chassis ground 56 GND Digital ground
Signal connections
Analog input
You can configure the analog inputs for SE or DIFF mode. The input voltage range is software selectable for
±10 V, ±5 V, ±2 V, or ±1 V.
With SE mode, connect up to 16 inputs to CH0 to CH15 . SE mode requires two wires:
 Connect one wire to the signal you want to measure (
CHx ).
 Connect one wire to the analog ground reference (
AGND ).
With DIFF mode, connect up to eight differential inputs to CH0H/CH0L to CH7H/CH7L . DIFF mode requires
two wires plus a ground reference:
 Connect one wire to the high/positive signal (
CHxH ).
 Connect one wire to the low/negative signal ( CHxL ).
 Connect one wire to the analog ground reference (
AGND ).
Floating voltage source
When connecting DIFF voltage inputs to a "floating" voltage source, make sure the DIFF input channel has a
DC return path to ground. To create this path, connect a resistor from each low channel input to an AGND pin.
A value of approximately 100
kΩ can be used for most applications.
Leave unused input channels either floating or tied to an AGND terminal. Source impedances should be kept as
small as possible to avoid settling time and accuracy errors.