Chapter 1
– 23 –
PCI-1721 User’s Manual
Advantech Co., Ltd.
www.advantech.com
3. Signal Connections
3.1 Overview
Maintaining signal connections is one of the most important factors in
ensuring that your application system is sending and receiving data
correctly. A good signal connection can avoid unnecessary and costly
damage to your PC and other hardware devices. This chapter provides
useful information about how to connect input and output signals to
the PCI-1721 via the I/O connector.
3.2 Analog Output Connections
The PCI-1721 provides four D/A output channels, Vout_0 ~ Vout_3
and Iout_0 ~ Iout_3. Users may use the PCI-1721 internally-provided
precision -5V (-10V) reference to generate 0 to +5 V (+10 V) D/A output
range. Users also may create D/A output range through external
references, REF_V0 ~ REF_V3. The external reference input range is
+/-10 V. For example, connecting with an external reference of -7 V will
generate 0 ~ +7 V D/A output.
Figure 3-1 shows how to make analog output and external reference
input connections on the PCI-1721.
Figure 3-1: Analog output connections
FIFO
MUX Data Bus
AGND
Load
Internal
External
+5 V
+
--
External Reference
For D/A Signal n
n: 0~3
REF_Vn
REF_INT
Vout_n
D/A n
Local Bus
Chapter
3
