FPGA & adaptive SoC databook · online editionRev. 2026.10

LFE5UM-85 vs XC6SLX75T

A comparison of the Lattice ECP5 LFE5UM-85 and the AMD Spartan-6 XC6SLX75T using the data from both vendors' selection guides.

Side-by-side specifications

LFE5UM-85XC6SLX75T
Vendor / familyLattice ECP5AMD Spartan-6
LUTs as published84,000 LUT446,648 LUT6
LUT type4-input look-up table6-input look-up table, fracturable into two LUT5 with shared inputs
LUT4 equivalent (approx.)≈84,000≈74,637
CoreScore (SERV cores)——
Vendor logic figure—74,637 LC
DSP156 18×18 multipliers132 DSP48A1 slices
Block RAM3.7 Mb3 Mb
Large RAM——
Max. user I/O365348
Transceivers4 × SERDES 3.2 Gb/s8 × GTP 3.2 Gb/s
Hard PCI ExpressNoneGen1 x1
Hard processorNoneNone
Process40 nm45 nm
Configuration memorySRAMSRAM
Packages43
Design toolLattice DiamondAMD ISE Design Suite

Highlighted values are higher. LUT counts are shown as published; the LUT4 equivalent is an approximation to compare different LUT types, see how FPGA vendors count logic. Add up to two more devices to this comparison.

Key differences

The LFE5UM-85 has about 13% more logic capacity (84K vs 74.6K LUT4 equivalents).

They use different logic architectures: the LFE5UM-85 is built from LUT4 and the XC6SLX75T from LUT6, so the raw LUT counts (84K vs 46.6K) are not directly comparable.

For arithmetic, the LFE5UM-85 has 156 18×18 multipliers against 132 DSP48A1 slices on the XC6SLX75T.

The LFE5UM-85 has more on-chip memory (3.7 Mb vs 3 Mb).

The LFE5UM-85 is designed with Lattice Diamond; open source: F4PGA or Yosys + nextpnr-ecp5 with Project Trellis and the XC6SLX75T with AMD ISE Design Suite.

Full specifications

See the complete spec sheets with packages and grades: LFE5UM-85 (ECP5) and XC6SLX75T (Spartan-6).