ADLINK PCI-7200 - Manual (Page 34)

22 Installation
2.8 LPCI-7200S PCI Bus Signaling
Low-Profile PCI is a new PCI card standard for space-constrained
system designs. The new form factor has the same electrical pro-
tocols, PCI signals, and software drivers as standard PCI v2.2
expansion cards. However, the Low-Profile PCI bus interface only
supports 3.3V signaling. To support both 5V and 3.3V signaling,
LPCI-7200S implements 5V I/O tolerant bus switches to achieve
the I/O voltage transition. This allows LPCI-7200S to be used in
both 5V and 3.3V systems.
2.9 Onboard Pull-ups and Terminations in digital
input
The PCI-7200, cPCI-7200 and LPCI-7200S have 32 digital input
channels. Onboard pull-ups and terminations for digital input cir-
cuits may be needed for some applications. The pull-ups guaran-
tee a fixed input state when external connections are floating.
Schottky terminations can minimize undershoot/overshoot distur-
bances caused by reflection noise on high-speed bus lines. Table
2.1 lists the pull-ups and termination status of PCI-7200, cPCI-
7200 and LPCI-7200S. Figure 2.8 is the illustration of the pull-up
resistor and terminations on-board.
Table 2-3: Pull-ups and termination of PCI/cPCI-7200 and LPCI-7200S.
Pull-up resistor Terminations
PCI-7200 None None
cPCI-7200 None Schottky diode clamped to ground & power
LPCI-7200S 10k
Ω
Schottky diode clamped to ground & power