Expansion Connectors

Opal Kelly Pins is an interactive online reference for the expansion connectors on all Opal Kelly FPGA integration modules. It provides additional information on pin capabilities, pin characteristics, and PCB routing.

Pins can also generate constraint files (XDC) and help you map your HDL net names to FPGA pin locations automatically.

The Pins reference for the XEM8310 may be found at the link to the right. 

Connector Details

Three high-density, 80-pin expansion connectors are available on the bottom-side of the XEM8310 PCB. These expansion connectors provide user access to several power rails on the XEM8310, the JTAG and SYSMON interfaces on the FPGA, 149 I/O pins, and access to the GTY transceiver banks.

MC1 and MC2 are high-density expansion connectors on the XEM8310 with Samtec part number: BSE-040-01-F-D-A. MC3 is a high-speed expansion connector with Samtec part number: QSH-040-01-F-D-DP-A.

The table below lists the appropriate Samtec mating connectors for the BSE-040-01-F-D-A along with the total mated height:

SAMTEC PART NUMBERMATED HEIGHT
BTE-040-01-F-D-A5.00mm (0.197”)
BTE-040-02-F-D-A8.00mm (0.315”)
BTE-040-03-F-D-A11.00mm (0.433”)
BTE-040-04-F-D-A 14.00mm (0.551″)
BTE-040-08-F-D-A25.00mm (0.984”)

The table below lists the appropriate Samtec mating connectors for the QSH-040-01-F-D-DP-A along with the total mated height:

SAMTEC PART NUMBERMATED HEIGHT
QTH-040-01-F-D-DP-A5.00mm (0.197”)
QTH-040-02-F-D-DP-A8.00mm (0.315”)
QTH-040-03-F-D-DP-A11.00mm (0.433”)
QTH-040-09-F-D-DP-A 14.00mm (0.551″)
QTH-040-07-F-D-DP-A25.00mm (0.984”)

MC1

MC1 is an 80-pin high-density connector providing access to FPGA Banks 64 (HP) and 84 (HD). Bank 64 is powered by VIO1. Bank 84 is powered by VIO2.

Pin mappings for MC1 are listed on the pins page. For each pin, the corresponding board connection is listed. For pins connected to the FPGA, the corresponding FPGA pin number is also shown. Finally, for pins routed to differential pair I/Os on the FPGA, the FPGA signal names and routed track lengths have been provided to help you equalize lengths on differential pairs.

MC2

MC2 is an 80-pin high-density connector providing access to FPGA Banks 84 (HD), 86 (HD) , and 87 (HD). Bank 84 is powered by VIO2. Bank 86 and 87 are powered by VIO3.

Pin mappings for MC2 are listed on the pins page. For each pin, the corresponding board connection is listed. For pins connected to the FPGA, the corresponding FPGA pin number is also shown. Finally, for pins routed to differential pair I/Os on the FPGA, the FPGA signal names and routed track lengths have been provided to help you equalize lengths on differential pairs.

MC3

MC3 is an 80-pin high-speed connector providing access to GTY transceiver banks 224, 225, and 226. This includes connections to MGTREFCLK0 (224), MGTREFCLK1 (225), and MGTREFCLK0 (226). MC3 also provides access to FPGA Bank 67 (HP). Bank 67 is powered by 1.2V, which cannot be changed.

The provided REFCLK pins have on board AC coupling capacitors while the transceiver lanes are directly connected to MC3.

Pin mappings for MC3 are listed on the pins page. For each pin, the corresponding board connection is listed. For pins connected to the FPGA, the corresponding FPGA pin number is also shown. Finally, for pins routed to differential pair I/Os on the FPGA, the FPGA signal names and routed track lengths have been provided to help you equalize lengths on differential pairs.

FPGA Bank Connections

FPGA BANKHR / HPVOLTAGE RANGE(*)MCXVIOVREFI/O AVAILABLE
64HP0.95 – 1.90 VMC1VIO1VREF152 (including 4 GC pairs)
84HD1.14 – 3.40 VMC1 / MC2VIO224 (including 4 GC pairs)
86HD1.14 – 3.40 V MC2VIO324 (including 4 GC pairs)
87HD1.14 – 3.40 V MC2VIO324 (including 4 GC pairs)
67HP0.95 – 1.90 V MC31.2V25 (including 2 GC pairs)

(*) – Note: Voltage ranges specified here are the range supported by the FPGA bank itself, not the range of the power supply connected to the bank. For power supply ranges refer to Device Settings.

The supplied Bank 67 1.2V VCCO rail has a limited user capacity of 250mA. Care must be taken using this rail as any noise coupled into it could have effects on the behavioral performance of the DDR.

Setting the Expansion Connector I/O Voltages

The Artix UltraScale+ FPGA allows users to set I/O bank voltages in order to support several different I/O signal standards. High-efficiency switching regulators on the XEM8310 provides three adjustable bank voltages VIO1, VIO2 and VIO3. These are connected to the FPGA bank VCCO according to the table above. Please see the Device Settings page for information on configuring these voltages.

By default, 0-Ω jumper resistors have been installed that attach each VCCO bank to the on board VIO supply. If you intend to supply power to a particular I/O bank externally, you MUST remove the appropriate resistor first. Power can then be supplied through the expansion connectors.

The table below lists details for user-supplied I/O bank voltages

I/O BANKVIOEXPANSION PINSJumper Resistor
64VIO1MC1-1R86
84VIO2MC1-80R87
86, 87VIO3MC2-69R88

Clock Input Pins

Available clock pins are shown in the XEM8310 Pins Reference. You can use the filter options to display these pins.

JTAG

The JTAG connections on the FPGA are wired directly to the expansion connector MC2 with 4.7kΩ pull-up resistors on TDI, TCK and TMS. The JTAG signal voltage is 1.8V. An appropriate connector (such as a 2mm connector compatible with the Xilinx JTAG cable) is need on the attached peripheral to the XEM8310. Our BRK8310 has this connector and may be used as a reference.

MC2 PINFPGA PinCONNECTION
71Y10TDO
74AB12TDI
76AE12TCK
72AB10TMS

SYSMON

FPGA system monitor signals are are wired directly to the expansion connector MC2.

VREFP may optionally provide a precision reference for optimal performance of the ADC. See Xilinx UG580 UltraScale Architecture System Monitor for additional details.

By default, C168 is populated with a 0.1-μF decoupling capacitor so that an external voltage reference may be used. To enable the internal reference instead, the peripheral must short VREFP (MC2 pin 79) to GNDADC (MC2 pin 77). Alternatively, C168 could be replace with a 0-Ω resistor.

MC2 PINFPGA PinCONNECTION
79R14VREFP
75N14VCCADC (1.8V supplied by the XEM8310 via FB1)
77N13GNDADC (Connected to DGND via FB2)

VREFN (FPGA P13) is connected directly to GNDADC.

XADC

The Xilinx Artix UltraScale+ XADC feature is routed through two 100Ω resistors to the MC2 connector. There is a 2.2 n capacitor installed across the two FPGA pins for decoupling.

MC2 PINFPGA PINCONNECTION
78P14XADC_VP_C
80R13XADC_VN_C

Considerations for Differential Signals

The XEM8310 PCB layout and routing has been designed with several applications in mind, including applications requiring the use of differential (LVDS) pairs. Please refer to the Xilinx Artix UltraScale+ datasheet for details on using differential I/O standards with the Artix UltraScale+ FPGA.

FPGA I/O Bank Voltages

In order to use differential I/O standards with the Artix UltraScale+, you must set the VCCO voltages for the appropriate banks according to the Xilinx Artix UltraScale+ datasheet.

HD banks support LVDS inputs only. If internal termination is used, the bank voltage must be set to 2.5V. If internal termination is not used then the bank voltage may be set to any voltage between 1.2V-3.3V.

HP banks support LVDS inputs and outputs. The following table shows what the required bank voltages are for the LVDS direction and internal termination pairings:

LVDS dIRECTIONiNTERNAL tEMINATIONBANK VOLTAGE
OutputN/A1.8V
InputYes1.8V
InputNo1.0V-1.8V

Characteristic Impedance

The characteristic impedance of all routes from the FPGA to the expansion connector is approximately 50Ω.

Differential Pair Lengths

In many cases, it is desirable that the route lengths of a differential pair be matched within some specification. Care has been taken to route differential pairs on the FPGA to adjacent pins on the expansion connectors whenever possible. We have also included the lengths of the board routes for these connections to help you equalize lengths in your final application. Due to space constraints, some pairs are better matched than others.

Reference Voltage Pins (Vref)

The Xilinx Artix UltraScale+ supports both internal and externally-applied input voltage thresholds for some input signal standards. The XEM8310 supports these Vref applications on bank 64 (HP). Please see the Xilinx Artix UltraScale+ documentation for more details.

For Bank 64, the Vref pin is routed to expansion connector MC1 on pin 4.

VRP Pins

The XEM8310 routes the multi-purpose VRP pin on bank 64 (HP) to the MC1 expansion connector on pin 32 . To support certain IOSTANDARDs like MIPI on bank 64 you can remove the 0Ω R158 resistor, and insert a 240Ω resistor at R159 to connect to ground.

Bank 67’s (HP) VRP pin is connected to ground through a 240Ω resistor. Full access to bank 67’s T2U and T3L byte groups are accessible through MC3’s high-speed expansion connector.

Please see the UltraScale Architecture SelectIO Resources for more details about the VRP pin and IOSTANDARD support.

I/O State at Power On

Xilinx Artix UltraScale+ FPGAs support a weak pull-up state on all I/O pins from power on until first configuration. This behavior is controlled by the PUDC_B pin. By default the XEM8310 holds the PUDC_B pin high with a 1kΩ resistor at R125, disabling the weak pull-up on all I/O pins at power on. This behavior can be changed by inserting a 1kΩ resistor at R128 and removing the 1kΩ resistor at R125, pulling the PUDC_B pin to ground.