High Bandwidth Memory (HBM2) Interface FPGA IP User Guide

ID 683189
Date 3/29/2024
Public
Document Table of Contents

4.3. Pin Planning for the High Bandwidth Memory (HBM2) Interface Intel® FPGA IP

The High Bandwidth Memory (HBM2) Interface Intel® FPGA IP requires the following clock inputs:
  • UIB PLL reference clock – Reference clock input for the UIB PLL. There is one UIB PLL reference clock per HBM2 interface.
  • Core clock input – Fabric core clock, generated through an I/O PLL.

When the core clock frequency is one-half of the HBM2 clock frequency, the reference clock that drives the core I/O PLL should come from the same oscillator as that supplying the UIB PLL reference clock on the board for a given HBM2 interface.

Table 17.  Placement Requirements for PLL Reference Input Clocks
Signal Description Pin Placement Guidelines
pll_ref_clk

The HBM2 IP parameter editor allows the selection of the following I/O standards:

  • LVDS with on-chip termination
  • LVDS without on-chip termination

Refer to the Stratix® 10 General Purpose I/O User Guide and Stratix® 10 Pin Connection Guidelines for termination recommendations based on the I/O standard chosen for the UIB PLL reference clock.

Place this reference clock input on the UIB_PLL_REF_CLK_00 pins while using the HBM2 device on the bottom of the FPGA, or the UIB_PLL_REF_CLK_01 pins while using the HBM2 on the top of the FPGA.
ext_core_clk LVDS differential input clock for generating the fabric core clock. Instantiate the I/O PLL that generates the core clock for the HBM2 IP. Place the reference clock input on CLK_ pins to access the I/O PLL. You should select pins that are close to the UIB_PLL_REF_CLK input. You must instantiate the I/O PLL in the design flow. The output of the I/O PLL serves as the EXT_CORE_CLK.

Jitter Specifications for the Input Reference Clocks

Both the reference clock inputs should meet and not exceed the following time interval error (TIE) jitter requirements:

  • 20ps peak-to-peak
  • 1.42ps RMS at 1e-12 BER
  • 1.22ps at 1e-16 BER