STaRBoardSTaRBoard

Jamal RorieJamal Rorie

5/09/065/09/06

Physics 476Physics 476

Why do we need ToF info?Why do we need ToF info?

Used to determine Used to determine species of particlespecies of particle– Central Drift Chamber Central Drift Chamber

records pathrecords path– ToF records timeToF records time– B = 1.5TB = 1.5T– Apply Lorentz Force Apply Lorentz Force

LawLaw

Why do we need to upgrade?Why do we need to upgrade?

Currently Belle has a luminosity of Currently Belle has a luminosity of 1.6x101.6x103434 cm cm-2-2/s/s

New technique: crabbing the beamNew technique: crabbing the beam

Belle luminosity will be ~2-3x higherBelle luminosity will be ~2-3x higher

Background will be ~2-3x higher as wellBackground will be ~2-3x higher as well

Old ToF is not fast enough to handle this; Old ToF is not fast enough to handle this; a new technique must be testeda new technique must be tested

Data CollectionData Collection

TDC

Leading EdgeLo Level

Discriminator MeanTimer

1:3 Splitter

ADC

Leading EdgeHi Level

Discriminator

Leading EdgeLo Level

Discriminator

TDC

1:3 Splitter

Leading EdgeHi Level

Discriminator

ADC

PMT PMT

Timing SchemeTiming SchemeWhat did the PMT know and when did it know it?What did the PMT know and when did it know it?

Hi level - event triggerHi level - event trigger

Lo level - higher time resolution Lo level - higher time resolution

Readout SchemeReadout SchemeEvent trigger received

by STaR

Logic request to TDC

TDC polls for “hit” around requested time

TDC sends data,Logic queries ADC

No TDC data,Logic doesn’t query ADC

ADC sends data

COPPER I/O carries data downstream

Hit No Hit

COPPERCOPPER

COmmon COmmon Pipelined Pipelined Platform for Platform for Electronics Electronics ReadoutReadoutOne One standardized standardized card can card can control up to 4 control up to 4 boardsboards

STaR LayoutSTaR Layout

HPTDC

HPTDC

LAB3

LAB3

XC3S2000

COPPER

COPPER

16

16

CLK

The STaR BoardThe STaR Board

LABRADOR3LABRADOR38 8 Input ChannelsInput Channels

HPTDCHPTDC

332 input channels2 input channels– only 8 used when only 8 used when

configured for configured for high precisionhigh precision

Spartan3 Spartan3 456 456 pin pkgpin pkg(340 used)(340 used)

ADC BlockADC Block

ADCADC– LABRADOR3LABRADOR3

STaR takes in differential signal from STaR takes in differential signal from upstreamupstream– lower noiselower noise– modifications necessarymodifications necessary

Shaper to elongate signalShaper to elongate signal– Originally 3 GSPSOriginally 3 GSPS– Now 100-300 MSPSNow 100-300 MSPS

TDC, Logic, and I/O BlocksTDC, Logic, and I/O Blocks(not quite as exciting)(not quite as exciting)

TDCTDC– ECL-to-LVDSECL-to-LVDS– HPTDCHPTDC

LogicLogic– Spartan3 2000Spartan3 2000

I/O I/O – COPPERCOPPER

TestingTesting

Shaper TestShaper Test– Elongation goodElongation good– Standard delayStandard delay

confirmingconfirming

TasksTasks

CurrentlyCurrently– Firmware developmentFirmware development– Board populationBoard population

AheadAhead– Software developmentSoftware development– Firmware testingFirmware testing– FinalizationFinalization– KEK observations (mid-July)KEK observations (mid-July)

Online DocumentationOnline Documentation

http://www.phys.hawaii.edu/~jroriehttp://www.phys.hawaii.edu/~jrorie– SchematicsSchematics– UpdatesUpdates– CodeCode– DatasheetsDatasheets