Agilex™ 7 Device Family Pin Connection Guidelines: M-Series

ID 776197
Date 6/12/2024
Public
Document Table of Contents

1.5.2. R-Tile Transceiver Pins

Note: Altera recommends that you create an Quartus® Prime design, enter your device I/O assignments, and compile the design. The Quartus® Prime software will check your pin connections according to I/O assignment and placement rules. The rules differ from one device to another based on device density, package, I/O assignments, voltage assignments, and other factors that are not fully described in this document or the device user guides.
Table 16.  R-Tile Transceiver Pins
Pin Name Pin Functions Pin Description Connection Guidelines
IO_RCOMP_0_P_GXR Input External biasing resistor for R-Tile.

Connect a 150-Ω 1% resistor between the GXR_RCOMP_N_0 pin and GXR_RCOMP_P_0 pin of each R-Tile bank.

RCOMP_P + RCOMP_N total trace routing (package and board) resistance is less than 0.500 Ω.

In the PCB layout, do not route traces next to high speed clock/data aggressors. You are required to keep the maximum capacitance on RCOMP_P less than 5.0 pF.

If this tile is unused, leave these pins floating.

IO_RCOMP_0_N_GXR
I_PIN_PERST_N_GXR Input PCI Express* ( PCIe* ) Platform reset pin.

In a PCIe* adapter card implementation, connect the PCIe* nPERST signal from the PCIe* edge connector to each R-Tile transceiver bank I_PIN_PERST_N input.

Use a level translator to fan out and change the 3.3-V open- drain nPERST signal from the PCIe* connector to the 1.0-V I_PIN_PERST_N input of each R-Tile transceiver that is used on the board.

Provide a 1.0-V pull-up resistor to the I_PIN_PERST_N input as the nPERST signal from the PCIe* connector is an open-drain signal. You must pull up the 3.3-V PCIe* nPERST signal on the adapter card.

If the tile is unused, tie to GND.

In cases where two independent clock sources are used for 2x8 bifurcation mode, ensure that I_PIN_PERST_N is deasserted high after both reference clocks are stable.

REFCLK_GXR[R,L][14A,14C,15A,15C]_CH[0,1]P Input

Standard PCIe* High Speed Current Steering Logic (HCSL) reference clock input pins, specific to the R-Tile transceivers on the left (L) side or right (R) side of the device.

For more information about the supported pins, refer to the device pin-out file.

It supports HCSL I/O standard only, must be DC coupled.

You must connect a 100-MHz ±100 ppm reference clock to both reference clock inputs for x16 and 4x4 modes. These reference clocks must be derived from the same clock source. A fan-out buffer can be used but must meet a ±100 ppm requirement for Gen 5.

REFCLK_GXR[R,L] [14A,14C,15A,15C]_CH[0,1]N

For 2x8 modes, you can connect both reference clock inputs to the same clock source or connect to two independent clock sources.

Leave these pins floating if unused.

GXR[R,L] [14A,14C,15A,15C]_RX_C H[0:15]P Input

Transceiver receiver pins, specific to the R-Tile transceivers on the left (L) side or right (R) side of the device.

For PCIe* Gen 5 mode, use the lower 16 bits [15:0]. These pins also support NRZ encoding up to 32 Gbps.

For more information about the supported pins, refer to the device pin-out file.

Leave these pins floating if unused.
GXR[R,L] [14A,14C,15A,15C]_RX_C H[0:15]N
GXR[R,L] [14A,14C,15A,15C]_TX_C H[0:15]P Output

Transceiver transmitter pins, specific to the R-Tile transceivers on the left (L) side or right (R) side of the device.

For PCIe* Gen 5 mode, use the lower 16 bits [15:0]. These pins also support NRZ encoding up to 32 Gbps.

For more information about the supported pins, refer to the device pin-out file.

Transmitter pins must be AC coupled. Leave these pins floating if unused.
GXR[R,L] [14A,14C,15A,15C]_TX_C H[0:15]N