Download - DAQ Update

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DAQ Update

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DAQ Status

• DAQ was running successfully and stably in ’07 beam time

• Trigger bus scheme has proven to be very flexible– Added additional delayed trigger during beam time

• Event rate of 6 Hz (e) + ~10 Hz calibration events can be handled easily–Max. DAQ rate now is 30 Hz, 50 Hz with firmware

update–Dead time will be reduced by multi-event buffering

through firmware update–DAQ rate will be even higher with DRS4 (no calibration

necessary)

• DAQ rate was 0.6 TB/day (7 MB/sec)– Reduction from 9 MB/event to <1 MB/event– Further reduction to ~50% by gzip compression– 100 TB disk available for 2008

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DAQ scheme

TRG1 TRG2 TRG3 TRG9 DRS4 DRS5 DRS6 DRS7 DRS8

trigger & trigger type & event # LSB

busy

internal trigger & busy

SYSTEM01 SYSTEM02 SYSTEM03 SYSTEM04 SYSTEM05 SYSTEM06 SYSTEM07 SYSTEM08 SYSTEM09

Event Builder

SYSTEM

Logger

Front-end synchronization:• Trigger sent to all front-

ends• Trigger type & event

#LSB• Busy is wired-or of all FE• Check of event #LSB at

event builder

Front-end synchronization:• Trigger sent to all front-

ends• Trigger type & event

#LSB• Busy is wired-or of all FE• Check of event #LSB at

event builder

Flexible trigger bus• Added delayed trigger

during beamtime without H/W modification

• 2nd level trigger possible in future

Flexible trigger bus• Added delayed trigger

during beamtime without H/W modification

• 2nd level trigger possible in future

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Dec. 2007 dataset

TB

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DRS4 design

• DRS2 used 2007 successfully for all ~3000 channels, but remaining issues

• Temperature dependencies (solved by DRS3)

• Poor clock pulse (solved by DRS3) • “Ghost pulse” problem (will be solved by DRS4)

• DRS4 design

• started Jan. 2008

• fixes “ghost pulse” problem, higher bandwidth, smaller package

• integrated PLL • daisy-chaining of channels allows

1.6 GHz 3.2 GHz sampling speed (if needed) • Time plan

• finish design: end of March ’08

• chip production: April – June ’08

• mezzanine board prototype: May ’08

• mass production: July/August ’08

• replace DRS2 by DRS4 as boards become available

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DRS3 clock signal

DRS2 clock (‘07 beam time)

RLVDSClock DRS2 chip

(single ended input)

DRS3 clock (last night ’07, 64 chn.)

RLVDSClock

DRS3 chip(differential input)

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“Ghost pulse” problem

R

“Ghost pulse”2% @ 2 GHz

“Ghost pulse”2% @ 2 GHz

After sampling a pulse, some residual charge remains in the capacitors on the next turn and can mimic wrong pulses

After sampling a pulse, some residual charge remains in the capacitors on the next turn and can mimic wrong pulsesSolution: Clear before write

write clear

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On-chip PLL

PLL

ReferenceClock (0.2-2 MHz)

Vspeed

~200 psec~200 psec

R. Paoletti, N. Turini, R. Pegna, MAGIC collaborationR. Paoletti, N. Turini, R. Pegna, MAGIC collaboration

External PLLExternal PLL

Internal PLLInternal PLL

• On-chip PLL should show smaller phase jitter• If <100ps, no clock calibration required• fclk = fsamp / 2048

• On-chip PLL should show smaller phase jitter• If <100ps, no clock calibration required• fclk = fsamp / 2048

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Daisy-chaining of channels

Channel 0 – 1024 cells








Domino Wave Generation

• DRS4 can be partitioned in 8x1024 cells or 4x2048 cells

• Smaller chip package of DRS4 allows 4 chips/mezzanine instead 2 DRS2

• Running with 2048 cell channels allow sampling speed of 1.6 GHz * 2 = 3.2 GHz with current trigger latency timing accuracy should improve ~2x

• Implement if necessary

• DRS4 can be partitioned in 8x1024 cells or 4x2048 cells

• Smaller chip package of DRS4 allows 4 chips/mezzanine instead 2 DRS2

• Running with 2048 cell channels allow sampling speed of 1.6 GHz * 2 = 3.2 GHz with current trigger latency timing accuracy should improve ~2x

• Implement if necessary