Chapter 4
Signal Connections
PCI-6023E/6024E/6025E User Manual
4-8
©
National Instruments Corporation
Analog Input Signal Overview
The analog input signals for these boards are ACH<0..15>, ASENSE, and
AIGND. Connection of these analog input signals to your board depends
on the type of input signal source and the configuration of the analog input
channels you are using. This section provides an overview of the different
types of signal sources and analog input configuration modes. More
specific signal connection information is provided in the section,
.
Types of Signal Sources
When configuring the input channels and making signal connections,
you must first determine whether the signal sources are floating or
ground-referenced.
PFI3/GPCTR1_SOURCE
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI4/GPCTR1_GATE
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
GPCTR1_OUT
DO
—
—
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI5/UPDATE*
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI6/WFTRIG
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI7/STARTSCAN
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI8/GPCTR0_SOURCE
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
PFI9/GPCTR0_GATE
DIO
—
V
cc
+0.5
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
GPCTR0_OUT
DO
—
—
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
FREQ_OUT
DO
—
—
3.5 at (V
cc
-0.4)
5 at 0.4
1.5
50 k
Ω
pu
AI = Analog Input
DIO = Digital Input/Output
pu = pullup
AO = Analog Output
DO = Digital Output
Note: The tolerance on the 50 k
Ω
pullup and pulldown resistors is very large. Actual value may range between 17 k
Ω
and
100 k
Ω
.
Table 4-2. I/O Signal Summary (Continued)
Signal Name
Signal
Type and
Direction
Impedance
Input/
Output
Protection
(Volts)
On/Off
Source
(mA at V)
Sink
(mA
at V)
Rise
Time
(ns)
Bias
PCI.book Page 8 Wednesday, September 16, 1998 9:09 AM