OBC-Johnston
Onboard Computer
RESILIENCE IN SPACE COMPUTING
The Johnston OBC is a high-reliability satellite computer built around a Flash-based FPGA platform. It’s purpose-built for space missions where dependable performance, fault resilience, and long-term operation are critical.
KEY FEATURES
- Single-Board Flash-Based FPGA SoC Satellite Computer
- Multiple Boot Sources with Selectable Regions
- Mission-Tailored Design with Flexible Firmware Options
- Compact and Integrated for CubeSats and Small Sats
DESIGNED FOR SPACE ENVIRONMENTS
Johnston OBC leverages the Microchip SmartFusion2 SoC platform, offering immunity to SEUs and greatly reduced power consumption compared to SRAM-based alternatives. Its architecture is hardened for operation in radiation-prone environments and temperature-extreme scenarios, making it a trusted core for spaceborne systems.
SMART CONTROL FOR MISSION SYSTEMS
With support for a wide range of digital and analog interfaces—including up to 50 GPIOs and 32 ADC channels—the Johnston OBC enables advanced control and monitoring capabilities for satellite subsystems such as power management, thermal control, and AOCS. Designed with flexibility in mind, it adapts to the specific needs of each mission.
MISSION-GRADE INTEGRATION
- 3–5 Year Operational Lifespan in LEO
- Real-Time Current and Temperature Sensing
- Built-in Watchdog for System Recovery
- Triple Real-Time Clocks for Timekeeping and Redundancy
- Integrated Voltage Regulation with Hot Redundancy
PROCESSING ARCHITECTURE
- Microchip/Microsemi SmartFusion2 Flash FPGA
- ARM Cortex-M3 Core
- Optional Floating Point Unit (FPU) on FPGA
- Up to 150 DMIPS at 128 MHz (Max 166 MHz)
- Supports Keil MDK and SoftConsole via JTAG Debugging
MEMORY
- RAM: 64/128Mbits MRAM 64-bit width (32-bit+32-bit ECC)
- Nonvolatile Flash Memory:
- Total 24GByte pSLC eMMC (Triple 8G)
- 4Mbit Serial FRAM
- 256M Serial NOR
ENVIRONMENT
- Radiation Tolerance:
- Total Ionizing Dose: 30Krad (Si)
- Latch-up Immune
- SEE @ 60MeV
- Temperature & Pressure: -40 C to +85 C @ 10-8 bar
- Shocks: 2000g, 2000-10000Hz
- Random Vibrations: 14g(RMS) 3-Axis , 20~2000Hz
INTERFACES
- DIGITAL/ANALOG:
- GPIO (5V/3.3V) : 48
- ADC (-10V ~ +10V) : 32CH 16-bit, (+20V Range Available)
- DAC (0V~5V) : 2CH 12-bit
- Serial Interfaces:
- CAN2.0 Up to 1Mbps : 4
- Full-Duplex RS422/RS232 : 4
- Half-Duplex RS485 : 2
- RS232 : 4
- I2C : 1
- SPI : 1
BUDGET
- Dimensions: 200x110mm or 170x135mm
- Mass: 700gr
- Power Supply: 28V ±4V, Custom Range Available
- Power Consumption: 1W ~ 2W
