Signal Connections
Chapter 3
AT-MIO-16 User Manual
3-4
© National Instruments Corporation
Pin
Signal Name
Reference
Description (Continued)
43
OUT1
DIGGND
OUTPUT1—This pin is from the Am9513A Counter 1 signal.
44
SOURCE2
DIGGND
SOURCE2—This pin is from the Am9513A Counter 2 signal.
45
GATE2
DIGGND
GATE2—This pin is from the Am9513A Counter 2 signal.
46
OUT2
DIGGND
OUT2—This pin is from the Am9513A Counter 2 signal.
47
SOURCE5
DIGGND
SOURCE5—This pin is from the Am9513A Counter 5 signal.
48
GATE5
DIGGND
GATE5—This pin is from the Am9513A Counter 5 signal.
49
OUT5
DIGGND
OUT5—This pin is from the Am9513A Counter 5 signal.
50
FOUT
DIGGND
FOUT—This pin is from the Am9513A FOUT signal.
The signals on the connector can be grouped into analog input signals, analog output signals,
digital I/O signals, digital power connections, or timing I/O signals. Signal connection
guidelines for each of these groups are described in the following sections.
Analog Input Signal Connections
Pins 1 through 19 of the I/O connector are analog input signal pins. Pins 1 and 2 are AIGND
signal pins. AIGND is an analog input common signal that is routed directly to the ground tie
point on the AT-MIO-16. You can use these pins for a general analog power ground tie point to
the AT-MIO-16 if necessary. Pin 19 is the AISENSE pin. In single-ended mode, this pin is
connected internally to the negative input of the AT-MIO-16 instrumentation amplifier. In DIFF
mode, this signal is connected to the reference ground at the output of the instrumentation
amplifier.
Pins 3 through 18 are the ACH<15..0> signal pins. These pins are tied to the 16 analog input
channels of the AT-MIO-16. In single-ended mode, signals connected to ACH<15..0> are routed
to the positive input of the AT-MIO-16 instrumentation amplifier. In DIFF mode, signals
connected to ACH<7..0> are routed to the positive input of the AT-MIO-16 instrumentation
amplifier, and signals connected to ACH<15..8> are routed to the negative input of the
AT-MIO-16 instrumentation amplifier.
The following input ranges and maximum ratings apply to inputs ACH<15..0>:
•
Differential input range
±
10 V
•
Common-mode input range
±
7 V with respect to AT-MIO-16 AIGND
•
Input range
±
12 V with respect to AT-MIO-16 AIGND
•
Maximum input voltage rating
±
20 V for the AT-MIO-16 board powered off
±
35 V for the AT-MIO-16 board powered on
Warning:
Exceeding the differential and common-mode input ranges results in distorted
input signals. Exceeding the maximum input voltage rating may damage the
AT-MIO-16 board and the PC AT. National Instruments is not liable for any
damages resulting from incorrect signal connections.