Minutes of the 3rd LHC Electronics Board held on 11th March 1997.


P.Borgeaud, F.Corsi, H.Dijkstra, Ph.Farthouat, L.Foa, F.Formenti, G.Hall, M.Letheren, E.Petrolo, S.Quinton, V.Radeka, P.SharpChairman), U.Straumann part time), G.Stefanini, M.Turala.

Apologies:  W.Smith.

1. The minutes of the 2nd meeting held on 20th January 1997 were approved.

2. There were no matters arising.

3. Review of Progress on the 1997 LEB Workshop

Geoff Hall reported on progress by the local organizing committee for the workshop to be held at Imperial College, London from 22-26 September 1997. Approximately 600 copies of the poster and call for papers had been mailed and a workshop web site http://www.hep.ph.ic.ac.uk/leb97/) had been created and was being kept up to date. Nevertheless, it was felt that an announcement and information bulletin emailed via the mailing lists of the LHC collaborations was still necessary to reach all potential participants. Industry exhibits were being encouraged.

The proposed number of parallel working groups had been reduced from 16 to 12 in order to accommodate plenary sessions in which the convenors of the working groups would present summaries and open the discussion to all workshop attendees. A number of names were suggested as candidates for working group convenors. The Chairman undertook to circulate to members of the Board an updated list of the working groups and their proposed convenors. He called for further nominations for convenors, which should be made bearing in mind that this year's workshop is intended to place an increased emphasis on system aspects.

The deadline for the submission of abstracts is 2nd May. The Board decided that its next meeting should last for two days 20-21 May) in order give time to review the abstracts and set up the detailed workshop time-table. The unavoidable clash with the IEEE Real Time Conference in Beaune was again discussed, and it was agreed that Peter Sharp and Geoff Hall would liaise with the RT '97 organizing committee via Patrick LeDu in order to ensure that, as far as possible, topics of common interest were not programmed for the same days.

4. RD29 DMILL) Status Report

The Board acknowledged the excellent work of the RD29 DMILL consortium, which had successfully developed a radiation hardened technology optimized to the requirements of the LHC experiments for low-noise, mixed-signal ASICs. Using the MPW service provided by CEA/LETI, fully functional circuits had been designed, fabricated and tested by 17 institutes, and the radiation hardness goals had been achieved in absolute terms and also in terms of consistency and reproducibility.

The Board heard with satisfaction the report on the status of the transfer of the DMILL process from the CEA/LETI labs to the Matra-MHS fab at Nantes, which was proceeding very well. The DMILL process at MHS is expected to be stabilized by 15th April; the first MPW run is scheduled for 2nd April and final acceptance of the industrial transfer by the CEA is expected for October 1997. LHC production runs will then be possible; their availability is guaranteed by the terms of the technology licensing agreement until at least September 2005.

The Board congratulated the collaboration on the progress achieved and agreed to ask RD29 to submit a final status report after the formal acceptance of the DMILL technology transfer to Matra-MHS, probably in the third quarter of 1997.

5. Quality Systems for LHC Experiments.

In the open session Steve Quinton presented Quality Systems for LHC Experiments. He reiterated the essential points that he had made in a closed presentation to the Board at its meeting on the 20th January 1997, and extended the scope of that presentation by reporting on the benefits experienced since the introduction of an ISO 9001 approved Quality Management system in the Technology Department at RAL.

In the closed session Steve Quinton showed typical examples of formal project documents produced within the framework of the Quality Management system applied at RAL. In the discussion a number of psychological barriers to the acceptance of Quality Systems were identified, such as the false) perception that these formal methods are inappropriate to a research environment, or can not be applied in a multiple-institute collaboration. Nevertheless, it was also observed that some elements of Quality Systems, such as the writing of user requirements documents, the carrying out of design reviews, etc., are already practiced at some level in many LHC projects.

It was concluded that the successful introduction of Quality Systems would require a full commitment at all levels, particularly the senior management of both CERN and the LHC experiments.

The Board confirmed its previous conclusion that the strengthening and extension of these practices by the introduction of some form of formal Quality Management System would be very beneficial to the development of the electronics systems for the LHC experiments.

In view of the above and the fact that Quality Systems issues are obviously relevant to all aspects of the LHC experiments, the Board:
- requested the Chairman to report its conclusions to the LHCC
- requested the Chairman to raise the issue with the spokesmen for the LHC experiments.

6. A Mixed-signal ASIC and MCM Test System for LHC

Mike Letheren summarized the paper submitted to the Board concerning the IC test system which, at the meeting of 20th January 1997, the CERN microelectronics group had proposed to set up at CERN in order to cover the testing requirements for mixed-signal ASICs developed for LHC.  The paper gave detailed technical specifications, proposed a mechanism for managing access to the system by LHC development groups, described the planned support for users of the system, and gave a cost-benefits analysis of the investment.

After discussion the Board agreed:

That there exists a need within the community for at least one such comprehensive test system optimized for design verification of prototypes and the testing of low- to medium-volume production runs.

That the cost-benefits analysis fully justifies the required investment, and that the proposed access and user-support mechanisms would be sufficient to ensure equable sharing and efficient use of the resource.

The Chairman thanked the LHC collaborations for their efforts to compile a list of the microelectronics chips under development for each experiment and encouraged the experiments to complete and maintain these lists, and to ensure that for each ASIC a quantitative estimate of its required tolerance to radiation effects is included in view of the subject of the next section).

The Board concluded by unanimously endorsing the proposal.

7.  Addendum to P63 - Study of Radiation Tolerant Electronics

An addendum to the P63 proposal had been received. It attempted to clarify the main issues raised by the Board in the discussion following the open presentation at the meeting of 20th January 1997; namely:

-  The focusing of the objectives of the proposal.

-  A demonstration that, if successful, the radiation tolerant approach would result in a significantly lower overall cost than the alternative of using radiation hardened technologies for all on-detector ASICs.

The Board confirmed its view, based on the evidence presented, that all non-hardened electronics, including custom ASICs, commercial off-the-shelf COTS) components, and even power supplies, placed anywhere in the LHC caverns are potentially vulnerable to serious radiation damage effects. In view of this, the Board accepted the twin goals of the proposal.

-  To assess radiation tolerant design and layout techniques applicable to commercial submicron technologies and make them available to LHC design teams.

-  To establish a collaboration with specialists from the space agencies and draw upon their experience and databases of measurements on the radiation tolerance of COTS components.

The Board agreed that the proposed goals are highly relevant to the LHC experiments, and potentially offer viable and economically advantageous solutions to the radiation tolerance problem. However, the Board emphasized that results from the R&D must be available in time to be applicable in the LHC experiments.

The Board recommended approval of the proposal with the following milestones for the end of 1997:

 -  Assess the radiation tolerance of a 0.5 mm CMOS process, based on the results from specially designed radiation tolerant test structures and on the design and evaluation of prototype chips for the ALICE pixel and TPC detectors.

-  Carry out a preliminary study of the radiation tolerance of 0.35 mm and 0.25 mm CMOS processes using test structures and choose one of these technologies for further study in 1998.

-  Negotiate non-disclosure agreements for access to the space agencies' COTS databases, such that relevant information can be made available to the LHC experiments.

The Board noted that a successful outcome of the first goal of the proposal cannot be guaranteed in advance, and access to the space agencies' COTS component databases may not result in the identification of sufficiently radiation tolerant COTS components to implement the current LHC electronics plans.

The Board therefore strongly recommended that the LHC experiments should explore in parallel alternative system-level solutions to the radiation tolerance problem.

8. Recommendations on VMEbus standardization

The Board heard feedback collected from the LHC collaborations on the recommendations of the VMEbus Steering Committee VSC) concerning the issue of adopting the VIPA-recommended VME extensions versus continuing developments compatible with the existing non-standard) pool of VME equipment developed in Europe before the freezing of the VIPA standards for extensions for physics.

After due consideration of the feedback, the Board decided to endorse the recommendations of the VSC, which can be summarized as follows:

-  All future VMEbus developments for HEP should follow the recognized standards VME64, VME64 Extensions, VIPA).

-  Continue to support the existing base of equipment implemented with non-standard extensions Jaux connector etc.), but avoid further procurement of non-standard equipment.

9. Plans for Future Meetings:

The date of the next meeting has been shifted to avoid a clash with the Elba conference. Two days are reserved; one for the regular business, and one for finalizing the programme of the workshop. The meeting will take place on:  May 20-21 1997

Final Status reports from:

RD12 - Optical Timing Trigger and Control distribution system for LHC.
RD16 - Fermi - Front-end and Readout Microsystem for calorimetry at LHC.

Status report from:

RD23 - Optoelectronic analogue signal transfer for LHC detectors.

Submission of the RD19 pixels) status report has been delayed to September in order to allow results from on-going beam tests to be included.

Preparation for the London workshop : 

Selection of convenors for the parallel working groups
Review of abstracts and finalizing the workshop programme.