Transcript SEU tests of an 80 Mbit/s optical receiver

SEU tests of an 80 Mbit/s
optical receiver
F. Faccio, K. Gill, M. Huhtinen, A. Marchioro, P. Moreira, F. Vasey
CERN, Geneva, Switzerland
G. Berger
UCL/CRC, Louvain-la-Neuve, Belgium
Karl Gill/CERN
Outline
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Introduction: the optical receiver
The experiment
“SEU” results
System implications
Conclusions
Karl Gill/CERN
Introduction
• Optical receiver for the CMS tracker slow
control => data & clock (@ 80 Mbit/s)
• Tracker = radiation environment => PIN
diode & ASIC have to be radiation tolerant
• Influence of radiation on the BER
performance of the link?
Karl Gill/CERN
Optical receiver
Fermionics InGaAs/InP
PIN
diode
ASIC
in
Preamplifier
with AGC
Limiting
Amplifier
Chain
LVDS
Tx
out
• ASIC designed in commercial 0.25 mm using radiation
tolerant layout techniques
• Both photodiode and ASIC have been proven radiation hard
Karl Gill/CERN
Mounting with two photodiodes
Karl Gill/CERN
Experimental setup
Optical
attenuator
1310nm laser
transmitter
Single-mode
optical fiber
Optical
power-meter
Output
signal
Bit Error Rate tester Input
signal
Karl Gill/CERN
PIN
diode
Optical
receiver
circuit
SEU measurements at CRC
(Louvain-la-Neuve, Belgium)
• 59MeV protons (1-4•108 p/cm2s)
• lower energy with moderators
• 62MeV (106 p/cm2s) and 32MeV neutrons
(5•105 p/cm2s), 50% of neutrons within
2MeV from the peak
• different angles to the beam
• shielding either receiver or PIN diode
Karl Gill/CERN
InGaAs PIN diode
sensitive region
80mm
2mm
90 deg
45 deg
Beam
Karl Gill/CERN
20 deg
BER calibration
1.E+00
1.E-02
BER
1.E-04
1.E-06
at CERN
1.E-08
p irradiation room
1.E-10
n irradiation room
1.E-12
-38
-33
-28
Signal [dBm]
Karl Gill/CERN
-23
Irradiation results (1)
1.E-04
Cross-section [cm2]
1.E-05
1.E-06
1.E-07
1.E-08
1.E-09
1.E-10
1.E-11
p 59 MeV, 90 deg
p 59 MeV, 45 deg
p 30 MeV, 90 deg
1.E-12
-32.00
-27.00
-22.00
-17.00
-12.00
Signal [dBm]
Events in the PIN diode dominate the error rate!
Karl Gill/CERN
Irradiation results (2)
1.E-04
Cross-section [cm2]
1.E-05
1.E-06
1.E-07
1.E-08
1.E-09
p 59 MeV, 90 deg
1.E-10
p 59 MeV, 80 deg
1.E-11
p 59 MeV, 45 deg
p 59 MeV, 20 deg
1.E-12
-32.00
-27.00
-22.00
-17.00
Signal [dBm]
Karl Gill/CERN
-12.00
Irradiation results (3)
1.E-04
Cross-section [cm2]
1.E-05
1.E-06
1.E-07
1.E-08
1.E-09
n 32 MeV, 90 deg
1.E-10
p 59 MeV, 45 deg
n 62 MeV, 90 deg
1.E-11
n 62 MeV, 45 deg
1.E-12
-32.00
-27.00
-22.00
-17.00
Signal [dBm]
Karl Gill/CERN
-12.00
Summary
1.E-04
1.E-07
Direct ionization,
angle 20-80deg
Direct ionization,
angle 90deg
1.E-08
Nuclear interaction
Cross-section [cm2]
1.E-05
1.E-06
1.E-09
1.E-10
1.E-11
1.E-12
-32.00
-27.00
-22.00
-17.00
-12.00
Signal [dBm]
Karl Gill/CERN
BER
System implications
1.E+00
1.E-01
1.E-02
1.E-03
1.E-04
1.E-05
1.E-06
1.E-07
1.E-08
1.E-09
1.E-10
1.E-11
1.E-12
1.E-13
BER in the lab
BER estimated for 45 deg
-37
-32
-27
-22
Signal [dBm]
Karl Gill/CERN
-17
-12
Conclusion
• BER performance of the receiver system
is degraded!
• SEU observed under irradiation in the
form of bit-errors
• Events in the PIN diode dominate the rate
• Errors due to both direct and secondary
ionization, depending on Popt, angle of
incidence and particle nature
Karl Gill/CERN