3/FEB/2015G. Blanchot, F. Faccio, S. Michelis1 FEASTMP DCDC Converters G. Blanchot On behalf of the PH-ESE Power Project Team

Outline 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis2  Introduction to PH-ESE Power project.  Power ASIC Developments.  DCDC Modules.  Availability and production status.

DCDC Power Project: Introduction 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis3  The LHC Upgrade is setting new requirements to several detectors in terms of powering.  The increased LHC luminosity brings the increase of readout granularity: more channels.  The new electronics is powered at lower voltages, with larger front-end currents.  Although there is a need for more power and more current to be delivered to the detectors, there is no additional volume to put new power cables: carry more power in same cables volume.  Also, the losses in the power cables need to be contained to avoid bringing in new cooling devices for what there is no volume either: need for a more efficient power distribution.  The requirements listed above set the need for DCDC converters in the detectors front-end electronics.  Powering at LHC was only based on regulators: introduction of DCDC is new.  DCDC converters need to stand high doses of radiation.  DCDC converters need to stand intense magnetic fields.  DCDC converters shouldn’t induce noise into the front-end electronics.  The PH-ESE Power Project addressed these new requirements:  A radiation tolerant buck type converter ASIC was developed.  The use of custom air core magnetic components enable the operation in very large B fields.  EMC analysis resulted in very low noise inducing DCDC converter modules.

Buck Converter Power Distribution 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis4  Low Voltage, High current delivered as close as possible to the load.  Higher voltage, lower current driven from the back end to the detectors, resulting in lower heat losses and thinner cables.

ASIC Developments 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis5  Several ASIC prototypes were designed through different technologies and radiation hardening techniques.  Today, FEAST2 is the device delivered for Phase 1 upgrades, packaged in QFN32 enclosure.  HBD design enabled TID tolerance up to more than 700 Mrad.  Displacement Damage (neutrons) tolerance exceeds 5×10 14 n/cm 2. TID checks include: output voltage, efficieny, functional features and protection. Dose rate = 9 Mrad/h. DD checks include mostly the bandgap deterioration, directly linked to output voltage and efficiency. High dose rate effect only

ASIC Development 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis6  Single Event Burnouts, Single Event Transients and Single Event Upsets were sorted out by addition of protective functions or by addressing the source of the problem at design level.  Today the FEAST2 ASIC was tested with heavy ions with LET of up to 65 MeV.cm2.mg -1.  Events of 32 MeV.cm2.mg -1 will induce a transient voltage drop of 2 µsec of 20 % at most.

DCDC Modules 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis7

Existing Modules 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis8 Features - Input voltage range 5 to 12V - Continuous 4A load capability (dependent on output power level, limited to 10W) - Available in different output voltage versions from 0.9 to 5V (minimum achievable with the FEAST ASIC 0.6V) - Synchronous Buck topology with continuous mode operation - High bandwidth feedback loop (150KHz) for good transient performance - Over-Current protection - Input under-voltage lockup - Over-Temperature protection - Power Good output - Enable Input Fast acting fuse in series at the input of the module to protect the line in case of module failure - EMC: conducted noise compatible with Class-B CISPR11 requirements in most conditions of Vin and Iout - Shielded to make it compatible with operation in close proximity (1cm) to sensitive detector systems - Radiation tolerant: TID up to >200Mrad(Si), displacement damage up to 5x1014n/cm2 (1MeV-equivalent), absence of significant SEEs up to >65MeVcm2 mg-1 (only short SETs smaller than 20% of the nominal Vout are observed) - Magnetic field tolerance in excess of 40,000 Gauss Negative output from a positive input voltage Positive output voltage

Availability and Production 3/FEB/2015G. Blanchot, F. Faccio, S. Michelis9  FEASTMP converters are in production since summer  HALT lifetime controlled for temperatures between -40 to +130 degrees with 20 Grms.  All produced DCDC modules now undergo a burn-in sequence from 20 X (-40 to 130 degC).  All produced DCDC modules undergo electrical tests to certify output voltage accuracy, minimal efficiency and functionality of control features.  3600 DCDC modules were produced so far.  7000 DCDC modules ordered, and will be produced in next batches.  All test results recorded in database, accessible over the web.  FEASTMP-CLP is a low profile implementation, with same features.  Production not started yet.  This converter requires a specific motherboard connector (that we provide).  Same burn-in sequence will be applied.  CLP modules were ordered and will be produced in 2015 and 2016 in several batches.  There are no requests so far for the FEASTMN modules.  The DCDC modules are on sale at production cost:  35 CHF per module.  Motherboard connectors.  Cooling interface and accessories can be provided also.  Orders and info request to be directed at: