Transcript News on DC-DC converter ASICs

FEASTMP DCDC Converters
G. Blanchot
On behalf of the PH-ESE Power Project Team
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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Outline
 Introduction to PH-ESE Power project.
 Power ASIC Developments.
 DCDC Modules.
 Availability and production status.
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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DCDC Power Project: Introduction
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The LHC Upgrade is setting new requirements to several detectors in terms of powering.
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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.
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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.
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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Buck Converter Power Distribution
tON
T
V ×I
h= O O
VI × I I
VO = VI
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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Low Voltage, High current
delivered as close as
possible to the load.
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Higher voltage, lower
current driven from the
back end to the detectors,
resulting in lower heat
losses and thinner cables.
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ASIC Developments
TID checks include: output voltage, efficieny, functional
features and protection. Dose rate = 9 Mrad/h.
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Several ASIC prototypes were designed through
different technologies and radiation hardening
techniques.
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Today, FEAST2 is the device delivered for Phase 1
upgrades, packaged in QFN32 enclosure.
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HBD design enabled TID tolerance up to more than
700 Mrad.
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Displacement Damage (neutrons) tolerance exceeds
5×1014 n/cm2.
DD checks include mostly the bandgap deterioration,
directly linked to output voltage and efficiency.
High dose rate
effect only
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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ASIC Development
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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.
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Today the FEAST2 ASIC was tested with heavy ions
with LET of up to 65 MeV.cm2.mg-1.
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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
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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DCDC Modules
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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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
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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
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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: [email protected]
3/FEB/2015
G. Blanchot, F. Faccio, S. Michelis
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