ADM-PCIE-9V3 User Manual
3.10 GPIO Connector
The GPIO option consists of a versatile shrouded connector from Molex with part number 0878331220 that give
users with custom IO requirements four direct connect to FPGA signals.
Recommended mating plug: Molex 0875681273
Figure 14 : GPIO Connector Schematic
Figure 15 : GPIO Connector Location
3.10.1 Direct Connect FPGA Signals
Four nets are broken out to the GPIO header as two differential pairs. These signal are suitable for any 1.8V
supported signaling standards supported by the Xilinx UltraScale architecture. See Xilinx UG571 for IO options.
LVDS and 1.8 CMOS are popular options.
The direct connect GPIO signals are limited to 1.8V by a quickswitch (74CBTLVD3861BQ) in order to protect the
FPGA from overvoltage on IO pins. This quickswitch allows the signals to travel in either direction with only 4
ohms of series impedance and less than 1ns of propagation delay. The nets are directly connected to the FPGA
after the quickswitch.
Direct connect signal names are labeled GP0_1V8_P/N and GP1_1V8_P/N to show polarity and grouping. The
signal pin allocations can be found in
Complete Pinout Table
3.10.2 Timing Input
The first two pins of the GPIO connector can be used as an isolated timing input signal. Applications can either
directly connect to the GPIO connector, or Alpha Data can provide a cabled solution with an SMA or similar
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Functional Description
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