VERTEX 2002 Experience with Parallel Optical Link for the CDF Silicon Detector S. Hou for the DOIM...
-
date post
19-Dec-2015 -
Category
Documents
-
view
220 -
download
1
Transcript of VERTEX 2002 Experience with Parallel Optical Link for the CDF Silicon Detector S. Hou for the DOIM...
VERTEX 2002
Experience with Parallel Optical Linkfor the CDF Silicon Detector
S. Hou for the DOIM groupAcademia Sinica, Taiwan
VERTEX 2002
Introduction
DOIM: Dense Optical Interface Module
Byte-wide parallel optical link8-bits + clock53 Mbyte/sec, BER10-12
Transmitter :Laser-diode arrayASIC driver chip
Receiver :PIN-diode arrayASIC receiver chip
Multi-mode fiber ribbon
Laser, Electrical characteristics
Bit-error rate test
Aging test
Radiation Hardness
Implementation in CDF
VERTEX 2002
Transmitter: Laser diode
InGaAs/InP Edge-emitting laser diode :1550 nm wavelength12-ch diode array (9 used)250 m pitch20 mA/channel
Cleaved mirrorsFacet coating
Bare laser power: 1 mW/ch @20mAInsertion to fiber: 200 ~ 800 W/ch
Fabrication byChunghwa Telecom Telecommunication Laboratories
VERTEX 2002
Transmitter: driver ASIC
Custom design, biCMOS 0.8 m,AMSbipolar transistors only
Inputs :Diff. ECL or LVDS signals compatibledifferential 100 mVEnable by TTL low
Nine channels :Vcc-VLD across output transistor, 50 , laser control current consumption
At 3V, 20mA/ch nominal ~2mA/0.1V adjustable slope
VERTEX 2002
Transmitter assembly
Die-bond / Wire bondlaser-diode array on BeO submountdriver chip on substratefibers on V-groove
Alignmentfibers to laser emitting facets
VERTEX 2002
Receiver : PIN & ASIC
InGaAs/InP PIN diode :12-ch array, matching laser diode wavelengthby TL, Chunghwa Telecom.
Operation condition :50 ~ 800 W on, 10 W off1.1 W/module
Outputs :differential ECL, nine independent channels
VERTEX 2002
Receiver assembly
Die-bond / Wire bondPIN-diode array on Al2O3 submountdriver chip on substratefibers on V-groove
Alignment, fibers to PIN-diodes
VERTEX 2002
Transmitter characteristics
Transmitter tests :L-I-V and temperature 50 MHz diff. Inputs, 2.5V common mode 100 mV, 50% +DcycLaser light MT-12ST fanout & Tek O/E probe
VERTEX 2002
Laser diode: L-I-V
Laser light at 20, 30, 40oCwater-bath chiller precision ~0.1oCmeasured at substrate
I-V little temperature dependenceapproximately linear
L-V Drop with temperature
Duty cyclediff. Input 50%stable, little offset to 50%
VERTEX 2002
Laser diode: temperature
Light power vs. Temperature
Measured in stable cooling/heating process
Temperature at substrate precision ~0.1oC
Approximately linear drop to temperature
VERTEX 2002
Receiver response
Receiver connected to a Transmitter
Light power chosen forwide distribution
Light pulse width are consistent
Receiver ECL outputs
by a Tektronix diff. probe
Consistent duty cycles in favored operation range (2.8~3.2V)
Saturates for high light level
VERTEX 2002
Transmitter uniformity : light outputs
Production transmitterslight from pigtail at 30oCwide deviation channel-by-channelmainly due to insertion efficiency
Span within ~400 W ~72 W to the mean/module
Effect operation dynamic range in threshold, saturation limit
VERTEX 2002
Transmitter uniformity : light pulse widths
Ch-Ch Light power deviationIs approximately a const. scaling factorL-V linear fit, normalized slope to L(3V) indep. of light power
Light pulse width is uniform, ~1%, indep. of light power
VERTEX 2002
Receiver uniformity : ECL duty cycles
Two production batchesmonitored at 550 W & 970 Wlight pulse width 45%
ECL duty cycle is uniform48.1% at 550 W, (2nd batch)=0.7%
4% wider in 1st batch
due to chip tuning
Wide light input range Saturation monitored at 970 W
VERTEX 2002
Receiver uniformity : duty cycle deviation
Input lights~950 W, width 45%
for all channels
ECL outputs of a module
deviation to the mean ~1.5%
for both batches
VERTEX 2002
Bit-Error Rate test
BERT by FermilabPC ISA boards TTL toTbert, Rbert boards
At 63 MHz, minimum BER 10 –12
Burn-in 3-days on ASICs, diodes 1-day BERT
reject devices infant mortality
bad components fail quickly
VERTEX 2002
Accelerated Aging test
4 transmitters at 60oC, 330 days
Wear-out degradation0.15 0.08 W/day at 60oCno failure
Accelerating factor
F=exp(Ea/ kb) (1/T1 –1/T2)
F=29 for T= – 5oC
Failure due to light degradationMin transmitter spec 200 Wdown below receiver threshold 50 W~100 days at 60oC, or 8 years at – 5oC
90% C.L. for 0 failure, P=0.064 upper limit = 40 ch. In 3 years
VERTEX 2002
INER 30 MeV proton Irradiation
CDF requirement : 200 kRad tolerance
INER test beam : transmitter in DC mode.
fiber connection out of beam area, measuring L, T versus dose.
VERTEX 2002
Bulk damage, annealing
Bulk damage dominant, linear dep. to dose
Ratio of light drop is consistent for a module, indep. of light power
Degradation 10% for 200 kRad
VERTEX 2002
UC Davis 63.3 MeV proton
UC Davis test beam : 10 transmitters on two Port Cards
Examined after 200, 400 kRad, for L I, V measurements
Light degradation ~10% for 200 kRad
Similar I-V, L-V characteristics after irradiation,
slope for L vs. V degrades similarly.
VERTEX 2002
DOIM implementation : transmitters
Transmitters on Port Cards
Total 570 transmitters
128 Port Cards,
5 transmitter each board
VERTEX 2002
DOIM implementation : receivers
Receivers on FTM
10 receivers on each board, reading 2 Port Cards
VERTEX 2002
Status
570 pairs implemented
~10 % bit-error flaggedexcess light at -5oCoptical reflection, contactelectrical pin contact2% has fatal damage
is improving