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cobo_changes

Differences between CoBo 1.0v and CoBo 0.2v

  • Rocket IO GTX Transceiver improvements
    • Bank 12 is no longer used. All (3V3) signals on that bank have been moved to bank 20
      • Now banks 12, 15, and 22 are not used
    • Re-routed signals away from MGT VCC/GND
  • Improved board power and power management
    • VCCINT, VCC3V3, and VCC5V0 no longer require a 350Khz resonator. i.e. Sync is disabled
    • VCCINT now uses a 10A switching regulator instead of a 16A
    • Input capacitance now conforms with MicroTCA requirement. i.e. it doesn't exceed 800uF
      • (C113) and (C122) are now 220uF instead of 330uF
    • Improved Power up sequence
      • No longer uses an additional (U35) chip (TPS3808G09DBVR)
      • Power-up sequence used to be VCCINT → VCC3V3 & VCC5V0. Now it is VCC5V0 → VCC3V3 → VCCINT
        • This reduces a race condition when BPI booting from flash
        • DDR2 memory is powered up after VCC5V0 turns on
        • VCC3V3 Auto Track pin is connected to VCC5V0. VCCINT Auto Track pin is connected to VCC3V3
  • Mutant WSCA/SYNC signal is now on a CC pin
  • Footprint updates
    • (U36), (U38), and (U39) Switching regulators have updated hole sizes for better fitting
    • (SW2) HDT001 switch layout fixes
  • Changed Clocking (see CoBo Clocking)
    • CKRs traces from PLL to LVDS buffer and from LVDS buffer to VHDCI connector are now equal
    • CKWs traces from PLL to LVDS buffer and from LVDS buffer to VHDCI connector are now equal
    • On LMK04800 (U41) CLKin1 no longer uses MCH clock as an input. A dedicated oscillator is now used (X9)
    • re-arranged outputs on LMK04800 (U41)
  • Consistent labeling and naming scheme on Front panel
  • Move usb-uart (J3) foward i.e. closer to front panel
  • USB-UART (U60) is power thru USB
  • Add 0 ohm resistors between MAX3378EEUD+ and FPGA (LEMO)
  • Radianheatsinks INH35001-18/2.6K29+T710 is now used for Virtex-5
cobo_changes.txt · Last modified: 2014/05/23 14:08 by abunimeh