DC-DC Conversion Studies – Status Report from Aachen Tracker Upgrade Power WG Meeting February 13 th, 2009 Lutz Feld, Rüdiger Jussen, Waclaw Karpinski, Katja Klein, Jennifer Merz, Jan Sammet 1. Physikalisches Institut B, RWTH Aachen University

Personal Katja Klein2Status Report from Aachen Lutz Feld: team leader Waclaw Karpinski: electronics engineer –plus electronics workshop team Katja Klein: Helmholtz Alliance fellow (4-years from April 08) Jan Sammet: PhD student Two diploma students: –Rüdiger Jussen (DC-DC converter studies) –Jennifer Merz (Analysis of the material budget)

Funding Katja Klein3Status Report from Aachen We have joined the SLHC-PP project of the EU FP-7 program (Work Package 8: Tracking detector power distribution) In Germany, next 3-year BMBF funding period starts in July 2009  Have applied for invest money and positions  First feedback in May

Work Plan from Mid 2008 Katja Klein4Status Report from Aachen Investigation of system aspects of novel powering schemes –DC-DC conversion –Serial powering? Noise susceptibility measurements –Noise injection into silicon strip modules –Noise injection into DC-DC converters Contribute to the development & characterization of magnetic field tolerant and radiation hard DC-DC buck converters, in coll. with CERN PH-ESE group –Duplicate CERN test-stand for converter noise characterization –PCB development –Magnetic field test –Irradiation tests Simulation of material budget of different powering schemes

Work Plan from Mid 2008 Katja Klein5Status Report from Aachen Investigation of system aspects of novel powering schemes –DC-DC conversion –Serial powering? Noise susceptibility measurements –Noise injection into silicon strip modules –Noise injection into DC-DC converters Contribute to the development & characterization of magnetic field tolerant and radiation hard DC-DC buck converters, in coll. with CERN PH-ESE group –Duplicate CERN test-stand for converter noise characterization –PCB development –Magnetic field test –Irradiation tests Simulation of material budget of different powering schemes First round of system tests with comm. buck converters finished. No concrete plans; concentrate on DC-DC conversion.

Results summarized by Lutz in October meeting System Test with DC-DC Converters Katja Klein6Status Report from Aachen  Noise of Enpirion converters can be controlled by combination of shielding and filtering (LDO). --- No converter --- Converter --- Converter + 30  m Alu shielding --- Converter + LDO --- Converter + LDO + 30  m Alu shielding Studies with commercial buck converters documented in Jans thesis CMS TS-2009/003 “System Test Measurements with a DC-DC Conversion Powering Scheme for the CMS Tracker at SLHC”

Work Plan from Mid 2008 Katja Klein7Status Report from Aachen Investigation of system aspects of novel powering schemes –DC-DC conversion –Serial powering? Noise susceptibility measurements –Noise injection into silicon strip modules –Noise injection into DC-DC converters Contribute to the development & characterization of magnetic field tolerant and radiation hard DC-DC buck converters, in coll. with CERN PH-ESE group –Duplicate CERN test-stand for converter noise characterization –PCB development –Magnetic field test –Irradiation tests Simulation of material budget of different powering schemes Not yet done, still planned. Ongoing.

Noise Susceptibility Studies Katja Klein8Status Report from Aachen Goal: identify particularly critical bandwidth(s) for converter switching frequency Bulk current injection test-stand has been set up (Rüdiger)

Noise Susceptibility Studies Katja Klein9Status Report from Aachen Injection of I=70dB  A (3mA) into power lines (2.5V, 1.25V, differential/common mode) Results not quite as expected; current interpretation: APV25 on-chip common mode subtraction is again hiding the real system response Deconvolution mode; mean noise of one APV Mean noise of one APV; zoom Deconvolution mode; noise of strip 512 Noise of strip 512; zoom Peak at around 6-8MHz seen for edge strips, but not in mean APV noise 2.5V, Diff. Mode Results will be presented at the next meeting. ?

Work Plan from Mid 2008 Katja Klein10Status Report from Aachen Investigation of system aspects of novel powering schemes –DC-DC conversion –Serial powering? Noise susceptibility measurements –Noise injection into silicon strip modules –Noise injection into DC-DC converters Contribute to the development & characterization of magnetic field tolerant and radiation hard DC-DC buck converters, in coll. with CERN PH-ESE group –Duplicate CERN test-stand for converter noise characterization –PCB development –Magnetic field test –Irradiation tests Simulation of material budget of different powering schemes Done. Currently covered by CERN. Done. PCB for SWREG2 chip done; PCB development ongoing.

PCB Development Katja Klein11Status Report from Aachen Aim for compactness and low mass Study possibilities for efficient low mass shielding (e.g. Parylene-coating) Study and improve noise filtering First prototype being characterized New PCBs expected for April In addition: PCB with LTC3568 buck converter; switching frequency configurable up to 4MHz; in hands, to be tested Enpirion EQ5382D LDO LTC3026 3cm

Magnet Test Katja Klein12Status Report from Aachen Tests performed with 7T NMR-magnet at Forschungszentrum Jülich, close to Aachen Enpirion converter, CERN SWREG2, LBNL charge pump tested  both versions with air-core and ferrite coils Result: converters with air-core inductors and charge pump worked fine; converters with ferrite inductors stopped working or lost their efficiency U out = 2.5V Details will be presented at the next meeting.

Work Plan from Mid 2008 Katja Klein13Status Report from Aachen Investigation of system aspects of novel powering schemes –DC-DC conversion –Serial powering? Noise susceptibility measurements –Noise injection into silicon strip modules –Noise injection into DC-DC converters Contribute to the development & characterization of magnetic field tolerant and radiation hard DC-DC buck converters, in coll. with CERN PH-ESE group –Duplicate CERN test-stand for converter noise characterization –PCB development –Magnetic field test –Irradiation tests Simulation of material budget of different powering schemes  Presentation by Jennifer

Summary & Outlook Katja Klein14Status Report from Aachen Simulation studies are far advanced  presentation today Magnet test done Noise injection into modules to be finished PCB development continues; focus on low mass, low noise, shielding System test measurements are restarting Development of test-stand to study systematically the coupling of noise from air-core inductors to the modules Feedback from funding agency needed for longer timescale planning!