CMS ECAL VFE Production Qualification

Upgrading the CMS ECAL barrel for the HL-LHC requires replacement of all on-detector electronics, including 12240 Very-Front-End (VFE) cards employing CATIA and LiTE-DTU ASICs for amplification and digitisation of signals from ECAL's 61200 lead-tungstate crystals. All production VFEs undergo the same qualification procedure: functional testing, environmental stress screening, and calibration. We have received and functionally tested 13596 unique VFEs; two never passed our test criteria. Results for other VFEs are uniform and within expectations, demonstrating the excellent quality of the cards. Key metrics, such as a gain ratio of 10.21 ± 0.07 and power consumption of 1.805 ± 0.013~W, demonstrate high consistency across the batch.