FEASTMP DCDC Converters G. Blanchot On behalf of the PH-ESE Power Project Team

1. FEASTMP DCDC Converters • G. Blanchot • On behalf of the PH-ESE Power Project Team G. Blanchot, F. Faccio, S. Michelis

2. Outline • Introduction to PH-ESE Power project. • Power ASIC Developments. • DCDC Modules. • Availability and production status. G. Blanchot, F. Faccio, S. Michelis

3. DCDC Power Project: Introduction • 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. G. Blanchot, F. Faccio, S. Michelis

4. Buck Converter Power Distribution • 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. G. Blanchot, F. Faccio, S. Michelis

5. ASIC Developments • 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 5×1014 n/cm2. 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 G. Blanchot, F. Faccio, S. Michelis

6. ASIC Development • 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. http://project-dcdc.web.cern.ch/project-dcdc/public/Documents/FEAST2%20datasheet.pdf G. Blanchot, F. Faccio, S. Michelis

7. DCDC Modules G. Blanchot, F. Faccio, S. Michelis

8. Existing Modules • Positive output voltage • Negative output from a positive input voltage http://project-dcdc.web.cern.ch/project-dcdc/public/DCDCmodulesDatasheets.html 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 G. Blanchot, F. Faccio, S. Michelis

9. Availability and Production • FEASTMP converters are in production since summer 2014. • 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. • 11000 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: dcdc.support@cern.ch G. Blanchot, F. Faccio, S. Michelis