Chapter 3 Signal Connections
DAQCard-1200 User Manual 3-4 © National Instruments Corporation
The connector pins are grouped into analog input signal pins, analog output
signal pins, digital I/O signal pins, timing I/O signal pins, and power
connections. Signal connection guidelines for each of these groups are
described in the following sections.
Analog Input Signal Connections
Pins 1 through 8 are analog input signal pins for the 12-bit ADC. Pin 9,
AISENSE/AIGND, is an analog common signal. You can use this pin as a
signal ground connection to the DAQCard-1200 in RSE mode, or as a
return path in NRSE mode. Pin 11, AGND, is the bias current return point
for differential measurements. Pins 1 through 8 are tied, through 4.7 kΩ
series resistances, to the eight single-ended analog input channels of the
input multiplexer. Pins 2, 4, 6, and 8 are also tied to an input multiplexer
for DIFF mode.
The signal ranges for inputs ACH<0..7> at all possible gains are shown in
Table3-1. Exceeding the input signal range will not damage the input
circuitry as long as the maximum input voltage rating of ±35 V powered on
and ±25 V powered off is not exceeded. The DAQCard-1200 is guaranteed
to withstand inputs up to the maximum input voltage rating.
Warning Exceeding the input signal range distorts input signals. Exceeding the maximum
input voltage rating may damage the DAQCard-1200 and the computer. National
Instruments is NOT liable for any damages resulting from such signal connections.
45 CLKB1 DI DGND Clock B1—External control clock signal for counter B1.
46 OUTB2 DO DGND Counter B2—Voltage output signal of counter B2.
47 GATB2 DI DGND Gate B2—External control signal for gating counter B2.
48 CLKB2 DI DGND Clock B2—External control clock signal for counter B2.
49 +5 V DO DGND +5 Volts—Fused for up to 1 A of +5 V supply, but limit
current to 250 mA.
50 DGND N/A N/A Digital Ground—Voltage ground reference for the digital
signals and the +5 V supply.
*Indicates that the signal is active low.
AI = Analog Input DI = Digital Input DIO = Digital Input/Output
AO = Analog Output DO = Digital Output N/A = Not Applicable
Pins Signal Name Direction Reference Description