wiki:RoblyerDOSIRackMount

This page describes a 2017 project to develop a second-generation D-DOSI system.

Conceptual Design

New Design

Current Prototype Reference Materials

2018-10-30 Check for mfg

2018-10-08 Edits

  • Created SVN tag 'RevA' from trunk, editing in trunk.

ECO list below including Dan's from 8/13/18

Editing in ...hardware/CARRIER/DSN

  • Slots 2, 3, 4 for DDS need LA02 and LA04 wired while on carrier LA02 and LA03 are wired (done)
  • Add level shifters on SPI for the Si5340 from 2.5V to 1.8V (done, added U101 and U102)
    • Note default Si5340 is 1.8V (can set to 3.3V using SW bit). PicoZed bank 13 is 2.5V.
  • Level shifters on FTDI serial are reversed! (done, ugh)

2018-08-13 Requests

  • On sheet 10 of Carrier schematic (all below done 10/8/18)
    • Connect CKIN_P0 to BANK13_LVDS_1_P
    • Connect CKIN_N0 to BANK13_LVDS_1_N
    • Connect CLK_P2 to BANK13_LVDS_0_P
    • Connect CLK_N2 to BANK13_LVDS_0_N
    • Connect CKIN_P1 to JX2_LVDS_12_P
    • Connect CKIN_N1 to JX2_LVDS_12_P
    • Connect CLK_P3 to BANK13_LVDS_8_P
    • Connect CLK_N3 to BANK13_LVDS_8_N
  • Please add "FPGA DONE LED" circuit from PicoZed FMC carrier board Page "07 - Switches, LEDs" pdf

2/10/18 To-Do

ADC board Layout check

  • Fab Drawing (stack-up):
    • change L1-L2 and L3-L4 dielectric to 5 mils
    • change L2-L3 to omit dielectric thickness spec so "DIELECTRIC - FR-4"

DDS board layout check

  • Fab Drawing (stack-up):
    • change L1-L2 and L5-L6 dielectric to 5 mils

Meetings

7/11/17

In meeting on 7/11/17 we discussed the development of a new version of the dDOSI electronics. The main differences from the existing hardware would be:

  • Compact rack-mountable design (target 1U enclosure height)
  • Variable gain and/or increased bit depth on ADC
  • Errors in prototype taken care of for easier manufacture
  • Update from MicroZED to PicoZED system-on-board

8/2/17

Candidate ADC is now ADS42LB69 dual-channel 16-bit 250MSPS converter

The PGA870 looks like a good candidate programmable-gain amplifier.

2/7/18

Meeting with Steven Larochelle, (Rachita Chaudhury), Thomas Floros, Darren and Raeef.

Decided:

  • Power supply connector is 6-pin 2x3 mini-fit Jr (DigiKey? WM11874-ND)
  • SMA connectors will all be vertical on the PCBs
  • Change GPIO design to include:
    • 4 SMA inputs
    • 4 SMA outputs
    • Header with 8 out + 4 in.
    • Change layout for vertical SMA connectors
Last modified 7 weeks ago Last modified on Oct 30, 2018, 3:23:06 PM