User`s manual

24 Hardware Information
2.2.1 Connector Signal Description
Table 2-4: CN1/CN2 I/O Signal Description
2.3 Analog Input Signal Connection
The USB-1901 and 1902 provide up to 16 single-end or 8
pseudo-differential analog input channels. You can set the Chan-
nel to acquire the desired input signal type combination. The ana-
log signal can be converted to a digital value by the A/D converter.
Signal Reference I/O Description
AIGND --------
Analog input (AI) ground. All three
ground references (AIGND, AOGND,
and DGND) are connected together on
board
AI<0..15> AIGND I
Analog Input Channels 0~15. Each
channel pair, AI<i, i+8> (I=0..7) can be
configured as either two single-end
inputs or one pseudo-differential input
pair (marked as AIH<0..7> and
AIL<0..7>)
CI<0..7> AIGND I
CI<0..7>+ and CI<0..7>- are differential
input pairs for current Input channel
0~7.
AISE(AISENSE) AIGND I
Analog Input Sense. This pin is the
reference for any channels AI<0..63> in
NRSE input configuration
AO<0, 1> AOGND O AO channel <0, 1>
GPI<0..7> DGND I
Function Input <0..7> (see Section 4.6:
Programmable Function I/O)
GPO<0..3> DGND O
Function Output <0..3> (see
Section 4.6: Programmable Function I/
O)
ECLK DGND I External A/D conversion clock
AITG DGND I Digital trigger for analog input
AOTG DGND O Digital trigger for analog output
NC NC NC No connection