Test Station for the LHCb Muon FrontEnd Electronics

1
Test Station for the LHCb Muon Front-End
Electronics
E. Polycarpo, G. Cernicchiaro, I. Bediaga, R.
Nobrega, L. Manhaes de Andrade Filho, A Machado,
J. Miranda, A. Reis, J. Magnin, F. Marujo, B.
Schmidt
Centro Brasileiro de Pesquisas Físicas - CBPF,
Brazil Universidade Federal do Rio de Janeiro -
UFRJ, Brazil CERN
Introduction
Front End Electronics Test FEET System
The LHCb Muon Group has developed the CMOS ASIC
CARIOCA to readout its Multiwire Proportional
Chambers (MWPC) and GEM detectors, using a
rad-hard IBM 0.25um process. Each ASIC holds 8
identical current-mode ASDB channels with
individual input thresholds. The Muon detector
contains around 120000 physical channels,
requiring production of 20000 front-end chips,
roughly. CARIOCA has been developed to process
MWPC cathode and anode signals and two different
versions have been implemented to overcome the
requirement of MWP and GEM chambers operation.
The test station has been devised to accomplish
bipolar tests and to measure characteristics of
both CARIOCA versions

• Tested Parameters
• Connectivity
• Power consumption
• Sensitivity and offset
• Noise
• Time response and width

Laboratory infrastructure
System
Separate ground lines for computers and power
supplies, temperature control, workbenches with
ESD protection equipment, grounded cupboard to
store the chips.
Results



Conclusion
Identification of the fraction of failed chips
(dead channels) CARIOCA (111) CARIOCA GEM
(10) Failure rate due to connectivity or offset
deviations CARIOCA(61) (with offsetlt10 and
sensitivitylt17.5) CARIOCA GEM (63) (with
offsetlt10 and sensitivitylt10.0) The
characterization rate is around 100 chips/day (1
station) The rate can be improved by robotization
and by optimization of the parameters for test,
instead of characterization
Overall Sensitivity
Current Consumption
Overall Noise

• Carioca Correlation Cut