Presenter: Curtis Grens April 3, 2003

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Presenter Curtis GrensApril 3, 2003
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Highlights of the Last Week

• Connectorized PD on current board replaced with
  unconnectorized PD
• Second board constructed, uses connectorized PD
• Baseline and attenuation tests repeated on second
  board.

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Attenuation Tests

• Discouraging RX results with 5dB attenuation.
• PD sensitivity? Damaged TIA? Cross-talk? Other?

Board 1 RX PRBS7 at 0dB
Board 1 RX PRBS7 at 5dB
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Board number 2.

• Board number 2 (right) Same design, same PD- new
  construction, new TIA.
• Board number 1 (left) Unconnectorized PD
  installed.

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Continued Testing

• Successful baseline test results for Board 2.

Board 2 RX PRBS7 at 0dB (with TX on)
Board 2 TX PRBS7 at 0dB
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Continued Testing

• Improved 5dB attenuation results for Board 2
• (RX shows improved attenuated performance with TX
  operating!!)

Board 2 RX PRBS7 at 5dB (TX unconnected)
Board 2 RX PRBS7 at 5dB (TX CONNECTED)
Board 2 Loopback PRBS7 at 5dB

• Based on left figure, damaged TIA ruled
  out. PD? Cross-talk?
• Board number 1 still awaiting functional XYZ
  stage.

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Plans for the Coming Week

• Further explore source of poor attenuated
  performance.
• Perform attenuation tests on Board 1 with the XYZ
  stage- determine if the superior unconnectorized
  PD improves attenuated performance.
• Determine if/which portions of the design could
  be modified/improved for finalized design.