GR740 Quad-Core LEON4 SPARC V8 Processor


The GR740 device is a radiation-hard system-on-chip featuring a quad-core fault-tolerant LEON4 SPARC V8 processor, eight port SpaceWire router, PCI initiator/target interface, CAN 2.0 interfaces and 10/100/1000 Mbit Ethernet interfaces.
The GR740 has been designed as the European Space Agency's Next Generation Microprocessor (NGMP) and is part of the ESA roadmap for standard microprocessor components. The GR740 is the first rad-hard implementation of the NGMP system-on-chip architecture.


  • System frequency: 250 MHz
  • Main memory interface: PC100 SDRAM
  • SpaceWire router with SpaceWire links 300 Mbit/s minimum
  • 33 MHz  PCI 2.3 initiator/target interface
  • Ethernet 10/100/1000 Mbit MACs
  • CCGA625 / CLGA625 / PBGA625 package


  • Fault-tolerant quad-processor SPARC V8 integer unit with 7-stage pipeline, 8 register windows, 4x4 KiB instruction and 4x4 KiB data caches.
  • Double-precision IEEE-754 floating point units
  • 2 MiB Level-2 cache
  • 64-bit PC100 SDRAM memory interface with Reed-Solomon EDAC
  • 8/16-bit PROM/IO interface, with EDAC in 8-bit PROM mode
  • SpaceWire router with eight SpaceWire links
  • 2x 10/100/1000 Mbit Ethernet interfaces
  • PCI Initiator/Target interface
  • MIL-STD-1553B interface
  • 2x CAN 2.0 controller interface
  • 2x UART, SPI, Timers and watchdog, 16+22 pin GPIO
  • CPU and I/O memory management units
  • Multi-processor interrupt controller with support for asymmetric and symmetric multiprocessing
  • SpaceWire TDP controller and support for time synchronisation
The GR740 device is targeted at high-performance general purpose processing. The architecture is suitable for both symmetric and asymmetric multiprocessing. Shared resources can be monitored to support mixed-criticality applications.

Software Support

We provide development tools such as the GRMON software debugger and various compilers and operating systems and a qualified boot loader for flight.

Quad-Core LEON4 Next Generation Microprocessor Development Board

The GR-CPCI-GR740 evaluation board has been designed for evaluation of the GR740 device:

The GR-VPX-GR740 Development Board is available for use with OpenVPX and SpaceVPX environments.

GR740 SBC Reference design
The GR740 SBC is a reference design for a single-board computer based on the GR740 and the Microchip RTG4 radiation-tolerant FPGA. 
The reference design data package consists of schematics and other design files required for developing a single-board computer for flight. 


The GR740 in ceramic package is available with QML-Q and QML-V qualifications.
The GR740 in plastic package is available with ECSS Q ST 60 13C class 2 qualification.
Detailed ordering information is described in the GR740-UM-DS.


Document File
GR740 SMD SMD 5962-21204
GR740 Data Sheet and User’s Manual
Documentation for GR740-CP, GR740-MP, and flight models.
GR740-UM-DS.pdf (November 2021)
GR740 Data Sheet and User’s Manual,
Documentation for prototype silicon (GR740-XX and GR740-YY) users.
GR740-UM-DS-1-10.pdf (July 2018)
GR740 Overview Presentation GR740-OVERVIEW.pdf (September 2018)
Comparison Between GR740, LEON4-N2X and NGMP GR740-CMP.pdf (August 2017)
GR740 pinout in Excel spreadsheet format GR740_pinout_rev1-6.xlsx (July 2020)
GR740 Technical Note on Benchmarking and Validation GR740-VALT-0010.pdf (April 2019)
GR740 PCB Design Package
Contains IBIS, BSDL, Package outline assembly drawings, Daisy-chain information
(password protected) (August 2019)
GR740 Power Calculator Spreadsheet GR740powercalculator.xlsx (February 2017)
GR740 Radiation Summary GR740-RADS-1-1-3.pdf (September 2020)
GR740 Product Brief GR740 Product Brief.pdf (June 2022)

Other Resources

A socket for use with prototype devices is available from Ironwood Electronics. The part number is C14992.