Hub SN-21 Trailer Sheet

24 FEB 2020
	- Begin work on Hub SN21 per instructions at /hub/hardware/details/Hub_Inventory_Status_Final_Assembly/hub_msu_final_assembly_prod_only_print.txt
		- Check GND/ESD continuity
		- Verify power supply resistances to GND
		- Preliminary mechanical work - mounting blocks, removing runners, etc.
		- Begin component R&R.

NOTE: During my initial inspection, I found a pin on IC U553 that hadn't soldered properly. The solder paste had somehow ended up on top of Pin 23, leaving a small solder blob there and Pin 23 not connected to Pad 23. Also, ceramic capacitor C1501 had suffered some kind of impact, leaving it cracked. Found the value as 100nF 0603 in the I2C Mentor Comps file and replaced the bad part with a 100nF 0603 that I have on hand for final assembly.

02 MAR 2020
	- Completed final assembly of Hub SN21
	- Work conformed to given instructions.
		- Installed RC filter components on MGT_AVCC, MGT_AVTT, and Fan_1V8 supplies.
		- Installed discrete power wires.
		- Installed light pipes and front panel.
		- Installed IPMC module #197
		- Installed minipods.
		- Installed MPOs.
		- Installed FPGA heat sink.
		- Installed fiber ribbons and clipped to side of heat sink.
		- Powered on and configured DC/DC converters.
		- Programmed with safe/foundation firmware.
		- Verified 25MHz, 40MHz, and 320MHz clocks with oscilloscope:

			PLL	Free Run  Hi-Lock  Lo-Lock
			------	--------  -------  -------
			40MHz	 40.09	  40.0845  40.0734
		       320MHz	320.7	  40.0820  40.0754


		- Final voltage measurements as follows:
	  
    		 Power Bus:      FPGA     MGT     MGT    Swch    Bulk     Fan    Bulk
       		                 Core    AVCC    AVTT     1V2     1V8     1V8     3V3
                       	         ----    ----    ----    ----    ----    ----    ----
       		   Address:       40      41      42      43      44      45      46
         	     Volts:     0.94     1.00    1.21   1.21    1.79    1.82     3.322
	              Amps:     0.95     0.00    0.19   1.88    0.56   12.06     1.625
	       Fluke Volts:     0.956    1.000   1.203  1.199   1.796   1.797    3.309

		- Removed IPMC bypass (yellow wire) after testing. IPMC module now has direct control of ISO_12V supply.

- Unit has been placed in the storage cabinet to wait for its turn in the 14SS.
	
24 APR 2020
	- Powered unit up on bench to update IPMC firmware.

06 AUG 2020
- This note is to confirm that this Hub has been cleaned with G3 flux remover.
  See
  l1calo/hub/hardware/details/Hub_Inventory_Status_Final_Assembly/FluxProblemOnHubs.txt 
  for details.

09 SEP 2020
- This note is to confirm that this hub has been through the component replacement process
  found at the bottom of the file in the above link.


23 SEP 2020
- This Hub has been mated with ROD V4 SN05

11 DEC 2020
- This Hub’s IPMC has been updated with the latest binaries.

06 MAY 2021
- This is a note to confirm that the board has been through the fiber ribbon replacement. See hub/hardware/details/Hub_Inventory_Status_Final_Assembly/Fiber%20Ribbon%20Problem/00_Hub_Fiber_Ribbon_Issue.txt for details.