Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. 9 th Workshop on Electronics for LHC Experiments. Amsterdam. September 29 th - October 3 rd, 2003

2 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 It is part of the electronics of the DT chambers of CMS muon detector: (Readout + Trigger). The aim is the time digitalization and data transmission to DAQ of the incoming signals from the Front-End electronics of the chambers. The first two levels of this data acquisition system are being developed at CIEMAT (Madrid, SPAIN): DDU USC55 Control Room DT chamber CMS DETECTOR Read Out Boards (ROB) Read Out Server boards (ROS) 30 m. LVDS copper link Towers 100 m. Optical link

1 Superlayer Φ 1 Superlayer θ Honeycomb 1 Superlayer Φ 1 Superlayer θ Honeycomb 1 Superlayer Φ 4 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003

Time measurement with respect to L1 Accept 5 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Drift Time t  x L1 Accept Latency Trigger 2314 Bunch crossing V drift ~ cte T max drift time ~400 ns >> T bunch crossing 25 ns 1234  Overlapping

40.08 MHz clock cm -2 s -1 luminosity, at 25 ns bunch crossing. 10 Hz/cm -2 charged particles rate. L1 Accept reduces to 1 Hz/cm 2 of muons => ~1 KHz/DT chamber cell. 250 DT-chambers, a total of 172,200 anode channels. Overlapping triggers due to a drift time of ~450 ns. Trigger latency of 3.2  s. Radiation hard devices are not going to be employed, radiation tests have to be performed to every component. 100 KHz triggers neutron fluence 10 years < cm -2 charged particles flux < 10 cm -2 s year integrated dose ~ 1 Gy Stray magnetic fields, in the barrel region around 0.08 Teslas. Limited maintenance for 10 years of operation. 6 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003

7 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Developed by the CERN/EP-MIC group, and produced by IBM in 0.25  m CMOS technology.  4 registers/channel before L1 buffer.  4 L1 buffers of 256 words, each shared by 8 channels.  Triggers stored in 16 words deep FIFO.  256 words deep readout FIFO.

8 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 LHC clock operation (40.08MHz). Highly programmable which provides flexibility. High integration, 32 channels per chip. Overlapping trigger handling. Trigger latencies (50 μs) large enough to accommodate our requirements (3.2μs). Time resolution of ~265 ps RMS in low resolution mode (Required resolution~1ns) Implemented in a radiation tolerant technology, up to levels of 30 Krad total dose with slight increase in power consumption. Up to 2MHz hit rates, much more than our needs (noisy channels ~ tens of KHz). Up to 1 MHz trigger rates, enough for 100 KHz maximum estimated. Bunch and event identification. JTAG port for programming and monitoring. Flexible read-out interface: parallel, serial or byte-wise. Error flags signalling lost of events, TDC internal errors, etc. and self-bypass on error.

9 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, HPTDC/ROB Compromise between #boards and #unused channels. READOUT INTERFACE DIAGRAM JTAG INTERFACE DIAGRAM   Clock synchronous token ring passing scheme where one TDC is configured as Master.   Bypass on error mechanism implemented.   An Altera FPGA manages the data_ready/get_data transmission protocol, slowing down the readout frequency to 20 MHz.   Clock synchronous token ring passing scheme where one TDC is configured as Master.   Bypass on error mechanism implemented.   An Altera FPGA manages the data_ready/get_data transmission protocol, slowing down the readout frequency to 20 MHz. Serializer parity) clock

10 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Power consumption: 2.5 V (0.5A) and 3.3V (0.5A) ~ 4 W. Power supply protection circuitry: In case of 2.5V current consumption over 1.5 A or 3.3V over 1A, power supply is disconnected, with powering on cycles every 700 ms (reduces to 10% power consumption). Sensor on board for temperature, 2.5V and 3.3V voltage and 2.5 V current monitoring. (Maxim DS2438). 32 bits/HPTDC word Master header and trailer Error signaling Timing and positional information (# TDC and # channel). Byte-wise readout (8 bits data+1 parity+2 byte ID) DS92LV1021 serializer (12 bits: 10 data + 2 start/stop) at 20 MHz.

11 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Master of the Data_Ready/Get_Data protocol slowing down readout to 20 MHz. Manages the channels enabling mechanism for testing chambers during spill interleaves, simulating artificial tracks. Triple redundancy registers have been implemented (solves 1 bit upsets) and a single event upset counter for radiation tests. Master of the Data_Ready/Get_Data protocol slowing down readout to 20 MHz. Manages the channels enabling mechanism for testing chambers during spill interleaves, simulating artificial tracks. Triple redundancy registers have been implemented (solves 1 bit upsets) and a single event upset counter for radiation tests. LVDS pair for ROB-ROS link LVDS clock signal ROBUS (RO-MC control bus) 128 LVDS signals from DT chambers channels (They are also retransmitted to trigger logic) Independent powering up signals (up to 7 ROB´s) ROB address lines JTAG lines other control lines (test pulses...)

12 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Time resolution: ~ 265 ps Neighbour channels crosstalk: Below half HPTDC bin resolution < ±0.35 ns Irradiation tests at the Cyclotron Research Centre (UCL): 5·10 10 p.cm -2 of 60 MeV protons. SEU: MTBF HPTDC = 3.8 days in the whole detector MTBF ALTERA = 3.4 days in the whole detector TDC can stand high hit rates, including noisy channels (~MHz) and this only affects 1 group of 8 channels. Test beams at Gamma Irradiation Facility (CERN): Oct. 01: test beam at GIF. Including a 25 ns structured beam May. 03: One full Minicrate operational. No errors found. Temperature cycling: Regulators (< 5mV/30ºC). 2.5 V current variations 0.4 mA/ºC. Time shift: 900ps/70ºC (14ps/ºC). Max variation ~40 ps/ºC. (30% due to LVDS-TTL receptors). Lifetime test: ROB fully operational at 105ºC ambient temperature for 4 months (3100 hours).

13 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 MB1 MB2 MB3 MB4 Link board MINICRATE TRB CCB Power supply 40A 1.5A 40 MHz CLOCK ROB RO- Link board ROB RO-link ROBUS Chamber signals TTC+Slow control to ROS 250 Minicrates 1500 ROB´s: Rob ROB-32 TRB SB

15 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 CPLD FPGA Equalizer CLC014AJE Deserializer DS92LV1212A FIFO IDT72V243 EqualizerDeserializerFIFO X 4 X 7 CPLD EqualizerDeserializerFIFOEqualizerDeserializerFIFO X Token ring # event GOL Optical Transmitter Memory 25 CHANNELS 1 wheel sector

16 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 ROB-ROS link: 30m copper AC coupled LVDS link RJ-45 cable from ROB´s. Link bandwidth: 240 Mbps. Throughput: 16Mbps. Measured BER < ROS-DDU link: 100m optical link to DDU in USC55 control room. GOL: 8B/10B Ethernet Slow (800 Mbps max. Bandwidth) 850 nm VCSEL Honeywell HFE419x-521 on 62.5/125  m multimode fiber LC conectorized. Link max. Bandwidth: 800Mbps. Throughtput: 270Mbps. ROB-ROS link: 30m copper AC coupled LVDS link RJ-45 cable from ROB´s. Link bandwidth: 240 Mbps. Throughput: 16Mbps. Measured BER < ROS-DDU link: 100m optical link to DDU in USC55 control room. GOL: 8B/10B Ethernet Slow (800 Mbps max. Bandwidth) 850 nm VCSEL Honeywell HFE419x-521 on 62.5/125  m multimode fiber LC conectorized. Link max. Bandwidth: 800Mbps. Throughtput: 270Mbps. 9U board located inside racks in towers of the CMS detector. Its task is the multiplexation of the data coming from the ROB´s of one whole sector of each wheel. 9U board located inside racks in towers of the CMS detector. Its task is the multiplexation of the data coming from the ROB´s of one whole sector of each wheel. TOTAL:60 ROS: 12 ROS/wheel 25 channels/ROS it also accepts trigger data from the backplane for testing and synchronisation purposes. TOTAL:60 ROS: 12 ROS/wheel 25 channels/ROS it also accepts trigger data from the backplane for testing and synchronisation purposes. It also has a power supply protection circuit. A pooling is done by a CPLD every 4 links to align events and fasten transmission. A token ring connects all CPLD´s for data flow to optical link management. ROB data format is modified to include additional information like ROB number and ROB/ROS link status (transmission errors and unlocks). 1MB memory for testing and data flow snapshots for traceability in case of TX errors. It also has a power supply protection circuit. A pooling is done by a CPLD every 4 links to align events and fasten transmission. A token ring connects all CPLD´s for data flow to optical link management. ROB data format is modified to include additional information like ROB number and ROB/ROS link status (transmission errors and unlocks). 1MB memory for testing and data flow snapshots for traceability in case of TX errors.

17 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, Kbytes FIFO per channel. 1Mword deep memory. Data accessible from VME, stored on memory or transmitted through 800Mbps copper link. 6U VME board

18 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 Irradiation tests at the Cyclotron Research Centre (UCL): 5·10 10 p.cm -2 of 60 MeV protons. SEU: MTBF FIFO = 2.3 days in the whole detector MTBF EQUALIZ = 17.2 days in the whole detector MTBF DESERIALIZER = 10.6 days in the whole detector May 2003 Test beam at Gamma Irradiation Facility (CERN): 1 ROS-8 operated in VME mode connected to 1 Minicrate. No errors found.

19 “ Overview of the Read-Out System for the CMS Drift Tube Chambers.” Fernández-Bedoya C., Marín J., Oller J.C., Willmott C. Amsterdam. September 29 th - October 3 rd, th Workshop on Electronics for LHC Experiments. October 2 nd, 2003 The chosen architecture fulfil the experiment requirements of trigger and hit rate, radiation tolerance, limited maintenance and power consumption among others. The final architecture of the read-out system for the CMS drift tube chambers is presented. It consists on two types of boards: ROB ROB: for time digitalization ROS ROS: for merging data from ROB´s and transmitting to DDU.