Antenna Deployment System 2

Cubesat On-Board Computer

Cubesat Battery Pack

The IMT Cubesat on-board computer (OBC) is based on the latest COTS technologies available on the market. The processor is a high performance 32-bit, Microchip PIC32MZ M14K based on the MIPSTM core, with a maximum operating frequency of 200MHz. Three memory banks are provided with independent anti latch-up circuits.

The RAM banks use a standard Cellular RAMTM PSRAM chip of 16MB. The flash NOR memory bank uses the high-speed SQI while the flash NAND memory bank is controlled through the standard ONFI. Both the NAND and NOR flash memories are in Triple Redundancy configuration with Majority Voting. 

The OBC provides 32 analog channel inputs with hot redundancy on each channel : 16 inputs are available to users, the other 16 are devoted to internal computer telemetry data. Two oscillators with one more backup crystal contribute to mission reliability.

Another contribution to mission reliability is provided by the internal dual flash and RAM panels that allows live firmware update in critical missions. Standard interfaces like SPI, CAN bus, I2C and UART are provided with two channels for each type. USB 2.0 and enhanced JTAG interface are available for the EGSE (Electrical Ground Support Equipment). Two Real-Time Clocks and Calendars powered by solid-state lithium battery allow time keeping up to 5 days without external power. Dual watch-dog system and Dead-Man Timer are provided for critical missions reliability. Four PWM bidirectional outputs are available (i.e. to perform ACS functions).

Furthermore, an On-Board Camera Interface (OBCI) allows applications of on-board computer for earth observation missions.

BROCHURE

Physical Characteristics

Dimensions (l x w x h)

96 x 90 x 10 mm
Power
  • 300 mW (normal operation)
  • 3.3V single supply voltage
Mass (without Stack connector)38 gRadiation< 15 kRad (Si)
Random Vibration10 Grms (all axis)Life Time> 3 years
Operating Temperature-20°C to +70°CNon Operating Temperature-40°C to +85°C

Qualification and
Acceptance Testing

Test

Qualification TestAcceptance Test
FunctionalYESYES
VibrationYESYES
Mechanical ShockYESOn Request
Thermal CyclingYESOn Request
Thermal VacuumYESYES
X-Ray InspectionYESYES
Total Ionizing Dose YESNO
OBC - Cubesat
OBC - Cubesat
Cubesat Battery Pack

Performance Properties

Processor:

  • PIC32MZ M14K
  • 32-bit MIPS TM core
  • Up to 200 MHz, 330 DMIPS

Operating system:

  • FreeRTOS
  • Other Real-Time OS Micrium μC/OS-II/OS-III, THREAD-X) available on request
Memory:
  • 16MB Pseudo-Static RAM (expandable up to 64MB)
  • 64MB Flash NOR Memory (expandable up to 128MB) for housekeeping data
  • 8GB Flash NAND Memory for Payload data
  • Triple Modular Redundancy on NOR and NAND flash memory bank
  • Majority voting system on NOR and NAND flash memory bank
Interfaces:
  • 2x CAN 2.0B bus interface up to 1Mbps
  • 2x UART interfaces
  • 2x I2C interfaces
  • 2x SPI bus
  • Up to 16 selectable devices on SPI buses
  • Hi-Speed USB 2.0 type A
  • 4-wire MIPS® enhanced JTAG interface
  • On-board camera interface (OBCI)
  • Open Nand Flash Interface for NAND flash memory bank
  • Serial Quad Interface for NOR flash memory bank
  • Parallel flash memory interface (CellularRAMTM standard) for PSRAM
Connectors:
  • 104-pin CubeSatKit standard bus connector
  • Molex PicoBlade (tm) 1.25mm for other interfaces

Other features

  • Up to 16 selectable devices on SPI busses
  • 12-bit Analog to Digital Converter
  • Dual independent analog BUS front-end
  • Dual Sample&Hold with 32 channels redundant multiplexers
  • Analog front-end comparator
  • Auxiliary analog comparator
  • Up to 28Mega samples per second with six digital filters and comparators
  • 16 analog channels dedicated to on-board telemetry
  • 16 user available analog input channels
  • 4x dedicated anti latch-up circuits: MPU&logic, RAM, flash
  • NOR bank and flash NAND bank
  • Dual Real-Time Clock and Calendar with solid state battery backup to keep time up to 5 days without external power
  • MPU integrated and on-board temperature sensors
  • 4 PWM bidirectional outputs
  • Power monitor and power-on reset
  • Dead-Man Timer and dual Watch-dog timers

Applications

  • On-Board Computer for Cubesat / Nanosatellite
  • Support ADCS operations
  • Payload Data processing (imaging and scientific mission)