1394b Design for Gigabit Optoelectronic Data Communication

1
1394b Design for Gigabit Optoelectronic Data
Communication

• Group G9
• Tiffany Lovett, gte291r
• Tornya Moore, gte668r
• Presented By
• Mareisha Winters, gte824t
• ECE 4006 C
• Spring 2002

2
Objective

• Design Considerations for OE components
• Link Budget Analysis
• Testing Procedures

3
Design Considerations for the VCSEL

• Two candidates
• Honeywell HFE4380-521
• Honeywell HFE4384-522
• Threshold current-minimum amount of current
  needed for the VCSEL to emit light
• Slope Efficiency-tells how many amps it takes to
  produce a given power output
• Rise/Fall Times

4
Comparison of Two VCSEL Candidates
HFE4380-521
HFE4384-522
5
Design Considerations for the Photodetector

• Two candidates
• Lasermate RSC-M85A306
• Hamamatsu S5973
• Responsivity-measures how much light input is
  required to produce a given current
• Capacitance of the photodiode must not exceed the
  maximum input capacitance of the MAXIM board.
• Rise/Fall Time

6
Comparison of Two Photodiode Candidates
Lasermate RSC-M85A306  
Hamamatsu S5973
7
Link Budget Analysis

• Will the system work for the proposed link?
• For this project the purpose of the link budget
  is to determine whether the transmitter and
  receiver system provide sufficient current to
  drive the post amp.
• Link Budget Power Incident on Photodetector x
  Responsivity of the Photodetector
• Power Incident on Photodetector Modulation
  Current of Transmitter x Slope Efficiency of
  VCSEL Losses Due to Connectors and Fiber

8
Link Budget Analysis (Contd)


9
Testing

• The PIN photodiode and VCSEL will be connected to
  their own separate boards and connected via
  optical fiber. These boards will then be
  connected to the MAXIM Evaluation Kits.
• The two pieces of equipment that will be used to
  verify the functionality of the components are
  the Tektronix GTS 1250 Bit Error Rate Test Set
  (BERTS) and Tektronix 7000 Series Oscilloscope.

10
Testing (contd)

• The BERTS measures the bit error rate (BER) for a
  given transmission.
• The BER is the percentage of bits that have
  errors relative to the number of bits received.
• BER 10-12
• The oscilloscope displays the data stream as
  information is transmitted. The data
  transmission creates an eye pattern.
• The preferred sampling time is when the eye is
  opened the widest.