GR716B - LEON3FT Microcontroller

The GR716B is a radiation-hardened microcontroller featuring the fault-tolerant LEON3 SPARC V8 processor. Based on the GR716A design, the GR716B has been developed to provide higher computational performance and excellent communication interfaces.

This page describes a running development and no guarantees can be given concerning future product availability. All information on this page is subject to change without notice. Please click this link to sign up to receive notifications about product and documentation updates.



- System frequency up-to 100 MHz

- SpaceWire links up-to 200 Mbps

- CQFP132 hermetically sealed ceramic package

- Total Ionizing Dose (TID) up to 300 krad (Si) (TBC)

- Single-Event Latch-up Immunity (SEL) to LETTH > 118 MeV-cm2mg (TBC)

- Single-Event Upset (SEU) below TBD errors per device and day in space environment

- Support for single 3.3V supply




  • Fault-tolerant  LEON3 SPARC V8 processor
    • 192 KiB on-chip RAM with EDAC
    • LEON-REX – extension with 16-bit instructions: improved code density
    • Double precision IEEE-754 pipelined floating point unit
    • Memory protection units
    • Deterministic software execution: Multiple non-intrusive buses, fixed interrupt latency, cache-less architecture
  • 2x Real Time Accelerator (RTA)
    • Offload the main LEON3 of demanding real-time tasks
  • External EDAC protected 8-bit PROM/SRAM memory
  • SPI memory protected by EDAC and dual memory redundancy
  • Power-on-Reset and Brown-out-detection
  • FPGA supervisor for programming and scrubbing Xilinx Virtex5 and Kintex UltraScale
  • Programmable PWM interface with Analog/Digital Voltage control and motor control loop support
  • Programmable pulse-width-modulation DAC
  • On-chip Boot ROM for low-level initialization and optional self-testing, standby and application loading
  • Remote boot through SpaceWire RMAP, CANOpen, SPI slave or UART
  • Enhanced DMA controller with support for ‘if-else’ statements
  • Timers with Watchdog


  • 2-Port SpaceWire Router with time distribution support, 200 Mbps max bitrate
    • LVDS with extended common-mode,  Cold-Spare and Fail-Safe support
  • 10/100 Mbit/s Ethernet
  • MIL-STD-1553B interface
  • CAN-FD controller interface with CANopen support for remote boot
  • PacketWire with CRC acceleration support
  • Programmable Enhanced PWM with analog/digital voltage control loop support
  • SPI with SPI-for-Space protocols
  • UARTs, I2C, GPIO
  • Mixed General purpose inputs and outputs

Integrated Analog functions

  • 4x ADC: 11/14bit resolution, 500/80kSps, 4 diff or 8 single channels
  • 4x DAC: 12bit, 20Msps. 
  • 8x PWM DAC: 24bit, 25Msps.
  • 20x Analogue comparator: 20ns (60ns SET-hard)
  • PLL
  • Crystal Oscillator
  • Power-on-Reset and Brown-out-detection
  • 1.8V and 3.3V voltage monitors
  • LVDS transceivers with build-in reference
  • Rad Hardened voltage and current reference
  • Rad Hardened Low-drop regulators for single supply support
  • Rad Hardened external voltage references
  • Temperature sensor, Integrated PLL
  • On-chip regulator for 3.3V single supply

 Software Development Environment (SDE)

We provide compiler toolchains and development tools with GR716B-specific support such as the GR716B BSPs, GRMON support, and simulator CPU/IO models. The Bare-metal environment is free and open-source. The GR716-MINI board can be evaluated using the free GRMON3 evaluation version.

Our SDE for the GR716 consists of the following software components:

- BCC2 Bare-metal C/C++ GCC/LLVM toolchain environment

- GRMON3 hardware debugger

- TSIM3 GR716 instruction simulator

Memory support

  • 192KiB EDAC protected tightly coupled memory with single cycle access from processor and ATOMIC bit operations
  • Embedded ROM with bootloader for initializing and remote access
  • Dedicated SPI Memory interface with boot ROM capability
  • 8-bit SRAM/ROM I/F with support up to 16MiB ROM and 256MiB SRAM
  • Scrubber with programmable scrub rate for all embedded memories and external PROM/SRAM and SPI memories
  • Redundant boot memory (PROM/SRAM/SPI/I2C/NVRAM)
  • Application software container for checking software integrity using CRC
  • Boot from internal SRAM, external PROM/FLASH/SRAM/SPI/I2C memory

The GR716B microcontroller is currently in the development phase and there is no guarantee that a flight part will be developed, qualified or sold.


Document Link
GR716B Data Sheet and User’s Manual

GR716B-DS-UM (December 2022)