Very Forward Muon Trigger and Data Acquisition Electronics for CMS: Design and Radiation Testing 21 Sept 2012 Jason Gilmore Vadim Khotilovich Alexei Safonov Joe Haley

CMS Endcap Muon System  = 2.4  = 0.8 2TWEPP 2012 Focus on the innermost Cathode Strip Chambers: ME1/1 CSCs J. Gilmore

Overview of the CSC System TWEPP 20123J. Gilmore VME ME1/1, High-Eta ME1/1

Overview of the CSC System TWEPP 20124J. Gilmore VME ME1/1, High-Eta ME1/1 New: Increase to 7 CFEBs, all with fiber links

CSC: Frontend Trigger Problem Out-of-time PU induces deadtime at higher luminosity  look at PU100 Particular issue is the ME1/1 “TMB” building chamber track segments – Two aspects making ME1/1 special:  Very high occupancies  ME1/1 TMBs effectively serve two chambers (inner ME1/a, outer ME1/b) Need better FPGA to maintain efficiency – The algorithm is ready (V. Khotilovich) – Design of prototype TMB completed Improve muon trigger efficiency for |  |>2.1 – Rate increase compensated by requiring 3 station coincidence for |  |>2.1  With new TMB can do w/o efficiency loss  Needs firmware modifications in CSCTF 5TWEPP 2012J. Gilmore

6 Snap 12 Fiber Receiver - fibers from 7 DCFEBs Snap 12 Fiber Transmitter socket (used only on test boards) Signal-level translators 3.3 V to 2.5 V Virtex 6 FPGA + XF128 PROMQPLL Dimensions: 7.5” wide by 5.9” high 11.1 mm clearance from TMB main board CSC TMB Mezzanine 2012 TWEPP 2012J. Gilmore Finisar Transceiver, only on test boards

TMB Mezzanine Location 7TWEPP 2012J. Gilmore

Radiation Studies for New CSC Boards Will the new components survive the expected exposure in the CMS Endcap at HL-LHC? – Not just CSC trigger boards, but also for the front-end boards  DCFEBs and ODMB, as well as new TMB mezzanine  Expected 1 MeV neutron fluence: 3 *10 12 n/cm 2 over 10-years  9 krad dose, do tests up to ~30 krad level for 3-times safety factor Will the Single Event Upset rates be unacceptably high? – FPGAs, fiber links, etc. used in front-end boards  Expected 20 MeV neutron fluence: 2.7 *10 11 n/cm 2 over 10-years  Measure SEU cross sections for individual design elements Initial radiation testing was done in 2011 – Digital components were tested with 55 MeV protons  Performed at the Texas A&M University Cyclotron facility – Other components tested with ~1 MeV neutrons  At Texas A&M University Nuclear Science Center reactor  A series of 5 exposures to test 40 different components – Results to be published soon, paper accepted by NIMA Additional 2012 tests completed recently at UC Davis 8TWEPP 2012J. Gilmore

Voltage Regulator Radiation Tests Testing performed at the Texas A&M Nuclear Science Center – 1 megawatt reactor operating at 6 kW, provides 9.9 *10 8 n/cm 2 s Multiple samples of several COTS regulators, two exposures – First exposure represents ~10 HL-LHC year dose (10 krad) – Second exposure adds ~20 HL-LHC years, total of 30 year dose (30 krad) – Regulator performance tested before and after each exposure  Regulators were unpowered during exposure Some regulators showed no ill-effects – National Semi LP38501 and LP38853 – Micrel and – TI TPS74901 Others did not fare so well… – Maxim 8557 – Sharp PQ035ZN1, PQ05VY053, PQ070XZ – TI TPS75601, TPS75901 – No improvement seen with additional cool-down time More parts were tested later, all are summarized in following slides… 9TWEPP 2012J. Gilmore

Summary of All Reactor Tests (1) Part/Chip NameChip Type 10 krad Exposure Pass/Fail 30 krad Exposure Result Comments Maxim 8557ETEVoltage RegulatorPassFail 5 out of 6 die at 30 krads MIC69502WRVoltage RegulatorPass MIC49500WUVoltage RegulatorPass National Semi LP38501ATJ-ADJCT-NDVoltage RegulatorPass National Semi LP38853S-ADJ-NDVoltage RegulatorPass Sharp PQ05VY053ZZHVoltage RegulatorPassFailFails to regulate Sharp PQ035ZN1HZPHVoltage Regulator50% PassFailFails to regulate Sharp PQ070XZ02ZPHVoltage RegulatorFail Fails to regulate TI TPS740901KTWRVoltage RegulatorPass TI TPS75601KTTVoltage RegulatorFail Fails to regulate TI TPS75901Voltage RegulatorFail Fails to regulate ST Micro 1N5819diodePass ON Semi 1N5819diodePass 2N7000FET transistorN/APass AD8028AR High Speed, Rail-to-Rail Input/Output AmplifiersN/APass ADM812Voltage MonitorN/APass LM41211M5-1.2 Precision Micropower Low Dropout Voltage ReferenceN/APass LM4121AIM5-ADJ Precision Micropower Low Dropout Voltage ReferenceN/APass TWEPP J. Gilmore

Summary of All Reactor Tests (2) Part/Chip NameChip Type 10 krad Exposure Pass/Fail 30 krad Exposure Result Comments LM1C1ZN/APass MAX680CSA+5V to ±10V Voltage ConverterN/APass MAX664CSA Dual Mode 5V/Programmable Micropower Voltage RegulatorN/AFailDead MAX4372High-Side Current-Sense AmplifierN/APass MIC35302High-Side Current-Sense AmplifierN/AFailDead MIC37302High-Side Current-Sense AmplifierN/AFailDead MM3Z4V7CZener DiodeN/APass MM3Z5V1BZener DiodeN/APass PQ7DV10Variable Output 10A Voltage RegulatorN/APass TPS7A7001Very Low Dropout, 2A RegulatorN/AFailFails to regulate TWEPP J. Gilmore

Summary of All Reactor Tests (3) Part/Chip NameChip Type 10 krad Exposure Pass/Fail 30 krad Exposure Result Comments SN74LVC2T45 Two-bit Dual-supply Tri-statable Bus Transceiver N/APass ADM660ARCMOS Switched-Capacitor Voltage ConverterN/APass ADM8828Switched-Capacitor Voltage InverterN/APass ICL7660S-BAZSwitched-Capacitor Voltage ConverterN/AFailDead LTC1044CS8100mA CMOS Voltage ConverterN/APass MAX1044CSASwitched-Capacitor Voltage ConverterN/AFailDead MAX860-UIA "uMAX"Switched-Capacitor Voltage ConverterN/APass MAX861-ISASwitched-Capacitor Voltage ConverterN/APass TC1044SCOACharge Pump DC-TO-DC Voltage ConverterN/APass TC962COE High Current Charge Pump DC-to-DC ConverterN/APass TWEPP J. Gilmore

SEU Testing of COTS Components (1) Testing performed at Texas A&M Cyclotron – 55 MeV protons with uniform flux, collimated to 1.5” diam – Maximum proton flux ~3 *10 7 cm -2 s -1 – 45 to 90 minute runs on each target device, 5-10 kRad in these tests Two samples tested for each COTS component – Reflex Photonics 3.5 Gbps Snap12 Receiver: model r12-c01001  Random PRBG data Gbps on each of six links  FPGA drives data to Transmitter, fiber connects to Receiver and carries data back to FPGA  SEU cross section:  = (8.2 ± 0.3) *10 -9 cm 2  Also tested to ~30 krad TID at TAMU reactor: no problems – Reflex Photonics Snap12 Transmitter: t12-c01001  3.5 Gbps, tested for use in ODMB upgrade  PRBG data Gbps on six links   = (7.3 ± 2.4) * cm 2 – Finisar Optical Transceiver: ftlf8524e2gnl  4.25 Gbps, tested for use in DCFEB upgrade  Transmit randomized GbE data packets to PC   = (1.0 ± 0.3) * cm 2 13TWEPP 2012J. Gilmore

SEU Testing of COTS Components (2) Xilinx Virtex-6 FPGA: xc6vlx195t-2ffg1156ces – No SEU mitigation in firmware for this study  Goal is to measure cross section of individual FPGA elements  Determine where mitigation is necessary – GTX Transceiver (55% used)  PRBG data Gbps   = (7.6 ± 0.8) * cm 2 – Block RAM (74% used)  4 kB BRAM “ROMs” readout to PC   = (5.7 ± 0.6) *10 -8 cm 2 – CLB (38% used):  4 kB CLB “ROMs” readout to PC   = (3.7 ± 0.5) *10 -8 cm 2 TI Bus-Exchange Level-Shifter: sn74cb3t16212 – Randomized data patterns sent through all 24 signal paths – No SEU observed,   < 1.7 * cm 2 14TWEPP 2012J. Gilmore

Impact of the 2011 SEU Measurements How would these cross sections affect CSC operations in HL-LHC? – Snap12 Transmitter: < 1 SEU per year per link – Snap12 Receiver: ~1 SEU per week per link  These typically just affect a single data word – Finisar Optical Transceiver: ~7 SEU/day/link  Typically just affects a single data word  Low rate, less than one error in 3 *10 13 bits – FPGA GTX Transceivers: ~3 SEU/year/link – FPGA Block RAMs: ~9 SEU/day/chip  These typically affect a single bit in a single cell  Need to investigate mitigation for FPGA BRAMs – FPGA CLBs: ~6 SEU/day/chip  Need to investigate mitigation for FPGA CLBs TWEPP J. Gilmore

Recent 2012 Radiation Studies Testing at UC Davis Cyclotron – 64 MeV proton beam, flux up to ~1 *10 9 cm -2 s -1 – Many of the same parts from previous SEU tests were retested using the same circuit boards  Snap12 parts are the only exceptions  New Emcore transmitters were tested in 2012  All chips survived 30 kRad dose *  Monitored power for signs of latchup (none observed) Some FPGA tests included mitigation this time – Enabled native ECC feature in Block RAMs  BRAM test used Read & Write under software control  Software designed to distinguish each failure mode – CLB tests based on triple-voting system  CLBs were implemented as a system of shift registers  Given common inputs and checked against each other  Error counts were recorded in registers and monitored by software 16TWEPP 2012J. Gilmore

SEU Test Results 2012 (1) Reflex Photonics 3.5 Gbps Snap12 Receiver: r12-c01001 – Random PRBG data Gbps on each of eight links – These SEUs only caused transient bit errors in the data – 2012 SEU cross section result:  = (6.4 ± 0.2) *10 -9 cm 2 – Combined :  = 9.5 * cm 2 per link  Similar to 2011 result, about 40% smaller Emcore 3.3 Gbps Snap12 Receiver: EMRS1216 – Same PRBG test as above – 2012 SEU cross section result:  = (9.8 ± 0.2) *10 -9 cm 2  This gives  = 12 * cm 2 per link  Similar to Reflex Photonics combined result, about 30% larger Emcore 3.3 Gbps Snap12 Transmitter: EMTS1216 – Same PRBG test as above; tested two of these parts – These SEUs only caused transient bit errors in the data – 2012 SEU cross section:  = (1.7 ± 0.2) * cm 2  This gives  = 2.1 * cm 2 per link  Nearly double the 2011 result for Reflex Photonics transmitter  Still very low rate of SEUs, so not a concern 17TWEPP 2012J. Gilmore

SEU Test Results 2012 (2) Finisar Optical Transceiver ftlf8524e2gnl : Transmit side – Gigabit Ethernet packet transmission tests to PCI card, Hz  Bad or missing packets received at the PC are “transmit” SEUs – These SEUs caused lost GbE packets and rare “powerdown” events – 2012 SEU cross section result:  = (4.3 ± 0.3) * cm 2  About 6 times the 2011 result; consistent with *6 increase in link duty cycle – Correcting for real CSC transmitter duty cycle:  = 8.2 *10 -9 cm 2 per link  We expect to see ~1 SEU per link per day during HL-LHC running Finisar Optical Transceiver ftlf8524e2gnl : Receive side – New test in 2012, load the BRAMs with data and read them back  Errors read back twice the same way are “receive” SEUs – These SEUs only caused transient bit errors – 2012 SEU cross section:  = (7.5 ± 0.1) *10 -9 cm 2 per link  We expect to see ~1 SEUs per link per day – *Three Finisars tested: one died at 33 krad, another at 41 krad  The third chip survived with 30 krad TI Bus-Exchange Level-Shifter: sn74cb3t16212 – Still no SEU observed, result:   < 4.0 * cm 2 18TWEPP 2012J. Gilmore

FPGA SEU Results 2012 GTX Transceiver (55% used in FPGA) – Random PRBG data Gbps on each of eight links – These SEUs only caused transient bit errors in the data – 2012 SEU cross section result:  = (10 ± 0.8) * cm 2  Similar to 2011 result, ~50% larger, consistent with additional active links Block RAM (74% used in FPGA) – Built-in ECC feature was used to protect data integrity – Software controlled write and read for BRAM memory tests – No errors were detected in the BRAM contents: mitigation at work – 2012 SEU cross section:   < 8.2 * cm 2 CLB (43% used in FPGA) – Most of the logic is a shift register system with voting – Some of it was unvoted logic for control and monitoring  This masks the “mitigation” effect of voting somewhat – 2012 SEU cross section result:  = (6.0 ± 0.5) *10 -9 cm 2  Much smaller than 2011 SEU result, factor of 6 better: mitigation at work  With this we expect ~1 CLB SEU per FPGA per day 19TWEPP 2012J. Gilmore

Conclusion TMB Mezzanine development coming to a close – We have a design and production plan for new CSC electronics  This will maintain a high level of efficiency for the foreseeable future – Prototypes have been built & tested Good results from radiation tests – We have found satisfactory COTS parts to meet all our design requirements – Development work still needed in SEU mitigation firmware Final CSC ME1/1 Electronics production begins soon – Need over 500 DCFEBs, plus spares: starts next month – Need 72 each for new TMB and ODMB, plus some spares  Start producing these early in 2013 – Installation in CMS from June-August TWEPP 2012J. Gilmore