Single Fiber Optical IO on standard 0.35 um CMOS
Nan Marie JokerstMartin A. Brooke
Duke UniversityDepartment of Electrical and Computer Engineering
email: [email protected]
HUB
Asymmetric or symmetricbandwidth link in each direction
Home Interface
Emitter stacked on top ofdetector for bi-directional link
•Co-located, stacked thin film emitters and detectors for bi-directional interface
•Single fiber between the hub and home
•Alignment tolerant for low cost packaging
Si CMOS Receiver and Transmitter Circuits
Thin film emitterThin filmdetector
Optical fiber
Previousresult for co-locatedemitter/detector pair
Home Interface Implementation Using a Single Fiber Bi-Directional Fiber Link
Si CMOS Rxand Tx Circuits
Thin film emitterThin filmdetector
Optical fiber
• The co-location of the emitter and detector enables single fiber bi-directional communication
• For asymmetric, low cost interconnection, detector
will run at 1 Gbps, and LED emitter at ~100 Mbps.
For faster emitter, edge emitter and mirror will be
used.
Co-Located Emitter and Photodetectorfor Single Fiber Bi-Directional Link
Transceiver: Laser Driver and TIA
RCE InGaAs LED50 m diameter with 30m aperture
I-MSM GaAs PD 150 m detector diameter
Measurements from Circuit With Integrated Stacked Devices
I-MSM photoreceiver eye diagram at 1Gbps
RCE LED optical transmitter eye-diagram at 40 Mbps (LEDs are slow)