[ Home | Contents | Search | Start a new article | Reply | Next | Previous | Up ]
From: Jorgen.Christiansen@cern.ch
Date: 8/5/99
Time: 11:48:07 AM
Remote Name: 137.138.115.156
Remote User:
Dear electronic designers in LHCb I would like to invite those of you who have made some progress on the design of the front-end electronics to let me know if you would like to make a presentation in the electronics meeting ( At NIKHEF, September 15 9:00 - 13:00). This LHCb week we hope to finally fix a set of important L0 front-end parameters: L0 trigger rate: 1MHz Determined by performance of L0 trigger and cost of front-end electronics. 1MHz seems reasonable for the trigger performance and allows 32 detector channels to be multiplexed after the L0 accept. L0 derandomizer depth: Min 16 L0 derandomizer readout time: Max 900ns This combination results in a deadtime below 0.5% and gives good room for flexibility in the implementation of the different front-end systems. Buffer overflow control: Emulation of front-end in readout supervisor. L0 trigger gap: None (accept of consecutive triggers). All sub-detectors have acknowledged that they can handle consecutive triggers. A gap of one would result in a physics loss of ~3.4%. Consecutive triggers are also usefull for system calibrations and tests. There is to my knowledge not any strong disagreements about these parameters within LHCb so I expect the official decision on these to be quite straight forward (at least I hope so). Other subjects for electronics meeting: Preliminary placement of electronics in cavern. Requirements to L0 front-end electronics. I have worked on a requirements document for the L0 front-end which will be available soon. We will go through this point by point during the meeting. Planning of Front-end and DAQ workshop at CERN October 12-14 (11 - 15 if required). Best regards Jorgen