LEON3FT-RTAX Fault-tolerant Processor


The LEON3FT-RTAX processor is a SOC design based on LEON3FT core, implemented in the RTAX2000S radiation-tolerant FPGA. The processor is delivered as a programmed and tested RTAX2000S device, with several package and quality options. The combination of the RTAX2000S radiation-tolerance and the fault-tolerant capabilities of LEON3FT makes LEON3FT-RTAX suitable for any space application. To validate the fault-tolerance properties of the LEON3FT-RTAX design, a heavy-ion error-injection test campaign was carried in November 2005. The test was fully successful and confirmed the suitability of the LEON3FT-RTAX processor for critical space applications.

LEON3FT-RTAX functionality

In addition to the LEON3FT core, the LEON3FT-RTAX includes a number of application-specific IP cores. Several pre-define configurations are available to address different application requirements. All configurations have the same basic architecture, which includes the following functions:

  • LEON3FT processor with 8+4 kbyte cache
  • LEON3 Debug Support Unit
  • PROM/SRAM controller with EDAC
  • Interrupt controller for 15 interrupts
  • Timer module with two 32-bit timers and watchdog
  • Two UARTs with FIFO
  • 16-bit I/O port

The configurations are differentiated according to the following table:

Configuration  FPU
 MMU SDRAM SpaceWire 1553 CAN  Ethernet PCI
LEON3FT-RTAX-IC1 yes - - - 1 RT 1 - -
LEON3FT-RTAX-IC2 yes - - 2 - - - -
LEON3FT-RTAX-SC1 yes - - - 1 BRM - - -
LEON3FT-RTAX-SC2 - - yes 3 - - - -
LEON3FT-RTAX-SC3 - yes yes 2 - 1 - -
LEON3FT-RTAX-SC4 - yes yes - - - 1 yes
LEON3FT-RTAX-PC1  yes - yes 2 - - - -
LEON3FT-RTAX-PC2  yes - yes - - - 2 -

Performance and power

The configurations can be clocked up to 25 MHz over the full military temperature range (except LEON3FT-RTAX-IC1 and LEON3FT-RTAX-SC1 that are fixed to 24 MHz). This provides upto 20 DMIPS and 4 MFLOPS in configurations with an FPU. The power consumption depends on the application, and is typically 0.5 W at full processor load. In power-down mode, the processor power consumption is ~ 0.3 W.

Custom configurations

In addition to the pre-defined configurations, it is possible to order LEON3FT-RTAX devices with custom configurations. Such configuration can also include IP core from the GRLIB IP library which are not listed above. An NRE cost will be charged for the development of each custom configuration.

Packaging, quality and lead time

The LEON3FT-RTAX devices are shipped as pre-programmed and tested parts in all quality levels supported by Actel. Supported packages are CQFP352 and CCGA624. For prices and lead times, contact Cobham Gaisler sales.