cobo_changes
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Difference 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
cobo_changes.1400854353.txt.gz · Last modified: 2014/05/23 10:12 by abunimeh