CERN/LEB 98-1/LEB6
 
Minutes of the 6th LHC Electronics Board held on 9th January 1998.

 

Present:

P. Borgeaud, F. Formenti, Ph. Farthouat, L. Foa points 3 and 4), D. Gregorio point 5), G. Hall,
Th. Lagrange point 5), M. Letheren, I. Mardirossian point 5), E. Petrolo, S. Quinton, P. Sharp Chairman),
G. Stefanini, M. Turala.

 

Apologies:
                           F. Corsi, H. Dijkstra, V. Radeka, W. Smith, U. Straumann.   1. The minutes of the 5th meeting held on 31st October 1997 were approved.

2. There were no matters arising.
 
3. RD49 Status Report Study of the Radiation Tolerance of ICs for LHC)

The Board was impressed by the significant achievements reported by RD49 and stressed the importance to the LHC Collaborations of the various radiation tolerance issues being addressed.

Experimental confirmation has been obtained of the expected improvement of the intrinsic radiation tolerance of standard commercial CMOS technologies with scaling to the deep sub-micron region 0.25mm). Substantial additional enhancement of this intrinsic radiation tolerance has been shown to be possible by adopting special design rules for the layout of transistors. The validity of the "radiation tolerance by design" approach has been shown in an LHC demonstrator a pixel readout chip for ALICE which operated within specifications up to a total dose of 2 Mrad).

Potential problems at the LHC due to "Single Event Effects" and the newly discovered "low dose-rate" effect in bipolar devices have been recognized. Plans have been prepared for further investigation of these phenomena with the aim of establishing methods of mitigating their impact in custom ASIC designs.

The magnitude of the risks associated with the planned widespread use of Commercial-Off-The-Shelf COTS) components in the LHC experiments has become better appreciated, and the LHC Collaborations have started to review their architectures in view of the concerns highlighted by RD49. Beneficial contacts have been established with the Space Agencies and other specialized institutes with a long experience of designing and operating electronics systems in radiation environments.

The Board strongly recommends that the LHC Collaborations develop a policy for risk management and well-defined procedures for the radiation-tolerance qualification of electronic components and subsystems, power supplies etc. located on the outer detectors or in the caverns. The Board stressed that RD49 has an essential role to play in evaluating the risks and defining qualification procedures together with the Collaborations, but does not have the resources to systematically qualify specific COTS components on behalf of the Collaborations.

The Board underlined the crucial importance of the issues being addressed by RD49 and recommends that their program of work should continue for a second year with the proposed milestones. The Board encouraged the LHC Collaborations to organize a common Workshop on radiation-tolerant electronics in order to foster a wide awareness of the latest results and their implications and to help prioritize RD49s multiple milestones.
 

     P. Sharp to emphasize to the LHCC the importance of the
     radiation-tolerant electronics issues and the need for the LHC
     Collaborations to adopt adequate risk management policies and
     qualification procedures.  
4. Proposal for a common project on radiation-tolerant, high-speed optical detector readout
   links for the LHC experiments.

The Board heard a report from G. Stefanini, who together with Ph. Farthouat and E. Petrolo, had been requested in the 5th LEB meeting 31 Oct 97) to investigate the feasibility of setting up a common development for a radiation-tolerant, high-speed
>1 Gbit/s), low-power, low-cost, digital optical detector readout link. Several partial and uncoordinated developments, each targeted at the requirements of a specific detector, and generally based on the availability of a particular component, are underway in the community. However, for a number of different reasons there is concern about the probability of successful completion and long-term survival of some of these developments, as well as the costs of long-term support and maintenance of multiple solutions. A proposal was presented to set up a unified team at CERN to develop a complete serial link solution satisfying requirements of all detectors. The team will:

The proposal was supported by the electronics coordinators of CMS, where there is a requirement for a very large number of such links. On the other hand, ATLAS has an internal working group on optoelectronic links and has not yet decided on fundamental options serial versus parallel), has a requirement for many fewer links, and can accept less stringent requirements on power dissipation. For ALICE, F. Formenti said there was a need for radiation-tolerant detector readout links and that a synergy of the current non rad-tolerant) development with the proposed development would be desirable.

Even though ATLAS have different requirements and have not decided on a final strategy for their high-speed optical readout links, the Board underlined the advantages of adopting a common solution - economy of scale, reduction of development costs and reduction of resources needed for long-term support and maintenance.
 

5. Frame contracts for procurement of radiation-hardened microelectronics

As a result of independent discussions between a supplier of radiation-hardened ASIC technology and each of ATLAS and CMS, it has been proposed to draw up a "Frame Contract".  This would define technical and commercial conditions for procurement mainly based on a global estimate of the number of wafers, but split up into a number of separate orders, each of a different volume and spread over a period of several years.  Such a frame contract will be established as a result of a call for tender based on a specification of technical requirements, number of runs, their volumes and the expected spending profile in time, etc.
A draft specification has been proposed by ATLAS.  A discussion took place to see whether a common frame contract could be established in view of the fact that each Collaboration has different requirements numbers and volumes of different designs, spending profiles, etc.).
The Board encourages  the LHC Collaborations to attempt to draw up a common draft under the coordination of D. Gregorio CERN-SPL).

     F. Formenti to identify contact persons in ALICE and LHC-B.
 
6. Status of Preparations for the LEB Workshop Rome, 21-25 Sept. 1998)

The 1998 LEB Workshop will be held in the Physics Dept. University of La Sapienza, Rome.  E. Petrolo reported that the local organizing committee would be constituted from people from the INFN and La Sapienza.  The call for papers is expected to be sent out by e-mail by the end of January.  The Abstracts deadline will be set as 1 May.

Topics:

  7. Any Other Business

 The Chairman summarized his presentation to the 31st LHCC meeting on 5-6 November 1997 and reported on the discussion that took place. His report covered the material from the LEB meetings of 20th May and 31st Oct 1997:

The date of the next LEB meeting was confirmed for Thursday 26 February 1998.