14th CBM Collaboration Meeting Split 2009

Status of Front End Electronics

N-XYTER PCB &

Power Supply

Volker Kleipa,GSI Darmstadt

14th CBM Collaboration Meeting Split 2009

Topics

Investigations in DC power supplies

➲ DC/DC step down converter test➲ Alternative DC step down design

NYXTER FEB_D

➲ N-XYTER PCB Requirements for FEB_D➲ N-XYTER PCB Cooling Plate ➲ FEB_D N-XYTER Cooling➲ N-XYTER FEB_D PCB

Status

14th CBM Collaboration Meeting Split 2009

DC/DC step down converter test

First tests done with a supply supported by Floeth ElektronikSupply spec. was 15V to 3.3V, single phase step down DC/DC converter,equipped with an air coil switched at 150KHz, no additional filter.Environment was 1.5T generated with ALADIN magnet at GSILoad 0.5Ohm

Results:+ Supply is working at 1.5T +Efficency independent of magentic field- 70% efficency only- High noise generation independent from magentic filed

Our Requirements for switched DC/DC converters:• High effincency (low local heat generation) to replace linear regulators• Up to 2T magnetic fields means no ferrite shielded components• Low Noise distribution

14th CBM Collaboration Meeting Split 2009

Alternative DC step down design

• Multiphase design

• Further investigations will be the testing some Reference desings

• I.e. IR design IRDCiP2002-C, Converter 12V to 3.3V, >82% eff., 120A output with 12mVp-p ripple1MHz/phase• Coils with only 300nH will be replaced by air coils.

14th CBM Collaboration Meeting Split 2009

N-XYTER PCB requirements for FEB_D

• Raised bondpad pitch

• Separated LVDS and common mode signals

• NXYTER chip and PCB hardware with efficient and regulated cooling

• Additional diagnostic hardware

• Power control

14th CBM Collaboration Meeting Split 2009

N-XYTER PCB Cooling Plate

Cooling Block for FEB_B, FEB_C and FEB_D

Design and Picture by Carmen Simons

14th CBM Collaboration Meeting Split 2009

FEB_D N-XYTER Cooling

A copper plate will be fixed on the bottom PCB sideThe N-XYTER will be placed on this copper plate from top side

14th CBM Collaboration Meeting Split 2009

N-XYTER FEB_D PCB

Changed/added:

• Alternative connector forseparated LVDs and common mode signals• New bond pitch• Separated supply regulators • 0.3V LDOs used• PT100 sensor out• Testpoints• New power connector• I2C and SPI spike filter

I2C reads now:• Temperature • Current• Testchannels Slow, Fast

I2C RW:• Serial EEprom for data storage

14th CBM Collaboration Meeting Split 2009

Status

• Power supply tests will continue with new design

• FEB_D PCB is now ordered

• FEB_D assembly is open

• New cooling case design ready for FEB_B, FEB_C and FEB_D

14th CBM Collaboration Meeting Split 2009

Thanksfor your attention