In:
Journal of Instrumentation, IOP Publishing, Vol. 16, No. 12 ( 2021-12-01), p. P12014-
Abstract:
The CMS Inner Tracker, made of silicon pixel modules, will
be entirely replaced prior to the start of the High Luminosity LHC period. One of the crucial components of the new Inner Tracker
system is the readout chip, being developed by the RD53 Collaboration, and in particular its analogue front-end, which
receives the signal from the sensor and digitizes it. Three different analogue front-ends (Synchronous, Linear, and
Differential) were designed and implemented in the RD53A demonstrator chip. A dedicated evaluation program was carried out to
select the most suitable design to build a radiation tolerant pixel detector able to sustain high particle rates with high efficiency
and a small fraction of spurious pixel hits. The test results showed that all three analogue front-ends presented strong points, but also
limitations. The Differential front-end demonstrated very low noise, but the threshold tuning became problematic after
irradiation. Moreover, a saturation in the preamplifier feedback loop affected the return of the signal to baseline and thus
increased the dead time. The Synchronous front-end showed very good timing performance, but also higher noise. For the Linear front-end
all of the parameters were within specification, although this design had the largest time walk. This limitation was addressed and
mitigated in an improved design. The analysis of the advantages and disadvantages of the three front-ends in the context of the CMS
Inner Tracker operation requirements led to the selection of the improved design Linear front-end for integration in the final CMS
readout chip.
Type of Medium:
Online Resource
ISSN:
1748-0221
DOI:
10.1088/1748-0221/16/12/P12014
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2021
detail.hit.zdb_id:
2235672-1
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