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ButterStick

A compact Lattice ECP5 based development board with breakouts for lots of high-speed I/O and serdes.

With onboard DDR3, High Speed USB and Ethernet.

Latest Revision:

Previous Revisions:

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Hardware (r1.0)

  • ECP5 25F/45F/85F (BGA381 package)
  • USB 2.0 High Speed (480 Mbit/s)
  • Gigabit Ethernet
  • upto 8Gbit DDR3L RAM (dual rank)
  • 128Mbit QSPI FLASH Memory (Bitstream + User storage)
  • MicroSD socket (4 bit SD interface)
  • Onboard oscillators:
    • 30 MHz (ECP5's PLLs can create 60MHz,125MHz,etc.)
    • 25 MHz (RGMII PHY)
  • 0.1" pitch JTAG connector
  • 7x User RGB LEDs
  • 2x User Buttons
  • 2x Standard SYZYGY compatible connectors
    • Adjustable VCCIO 1.2V-3.3V
    • Up to 32 single ended I/O
    • 10 differential pairs
    • Dedicated clock input pins
  • 1x Transceiver SYZYGY compatible connector
    • Adjustable VCCIO 1.2V-3.3V
    • Up to 14 single ended I/O
    • 2x/4x Lanes TX (5 Gbps SERDES)
    • 2x/4x Lanes RX (5 Gbps SERDES)
    • 1x Reference clock input

Board dimensions: 80mm x 49mm

Variants

The ButterStick can be configured in different variants, the part number defines which FPGA and DDR3 parts are installed.

ButterStick-r1.0-[Memory gigabits]-[FPGA density]

ButterStick-r1.0-2G-25F ButterStick-r1.0-2G-85F ButterStick-r1.0-8G-85F
FPGA LFE5UM5G-25F-8BG381C LFE5UM5G-85F-8BG381C LFE5UM5G-85F-8BG381C
DDR3 2x MT41K64M16TW-107 2x MT41K64M16TW-107 2x MT41K256M16TW-107

The 25F also has the following limitations on the ButterStick:

  • 25F Only provides 2x SERDES lanes.
  • 25F does not connect I/O pins S8/S9 on SYZYGY.C

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Licence

  • Hardware in this repository is licensed under CERN OHL v1.2

Open Source Hardware

This board is an OSHWA approved design: AU000016