Calibration des Microroc (II) Alex, Cyril, Giom, Jean, Max 09 Mai - - PowerPoint PPT Presentation

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Calibration des Microroc (II)

Alex, Cyril, Giom, Jean, Max 09 Mai 2011, Annecy

1 Reminder 2 Comparison single chip & ASU chip 3 Chip to chip variations 4 Outlook

1 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Previous results (I)

Experimental conditions

Test charge: 2.5, 12.5, 25, 37.5 fC Pedestal offset at 7 Send charge to group of 8 channels

Pedestal offset

Reduction of pedestal RMS by factor 2

Preamplifier gain (4 chips)

∼ 7 DAC/fC with 1 % RMS variations (Small) channel to channel variations Noise of about 0.12 fC

2 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Previous results (II)

threshold (DAC unit)

180 185 190 195

efficiency (%)

20 40 60 80 100

Scurves - chip 8 ASU 14 - Tuned offset

hgain_8

Entries 64 Mean 6.989 RMS 0.06986

gain (DAC/fC)

6 6.5 7 7.5 8 5 10 15 20 25 30

hgain_8

Entries 64 Mean 6.989 RMS 0.06986

Preamp gain Microroc 8 ASU 14

channel

10 20 30 40 50 60

gain norm. avg.

0.96 0.98 1 1.02 1.04

Gain VS channel chip 8-20-32-45 ASU 14

Conditions for next tests

Test charge: 2.5, 12.5, 22.5, 32.5 fC Pedestal offset at 7 Send charge to single channels

3 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Comparison single chip & ASU chip

Production test

Flat pattern Wrong gain channel 8 Higher gain channel 62 & 63

channel

10 20 30 40 50 60

gain norm. avg.

0.95 0.96 0.97 0.98 0.99 1 1.01 1.02 1.03 1.04 1.05

• Norm. gain VS channel all chips ASU 15 - production

Recent ASU test

Periodic pattern Variations modulo 8 Higher gain channel 63

channel

10 20 30 40 50 60

gain norm. avg.

0.95 0.96 0.97 0.98 0.99 1 1.01 1.02 1.03 1.04 1.05

• Norm. gain VS channel all chips ASU 15 - calibration

4 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Channel to channel variations

Mean gain versus channel number

Periodic pattern observed for all fully tested ASUs (14, 15) Reflect lenght variation of PCB pad to pin lines Channels 62 and mostly 63 are clearly far from average

channel

10 20 30 40 50 60

gain norm. avg.

0.99 1 1.01 1.02 1.03 1.04

• Norm. gain VS channel all chips ASU 15 - calibration

5 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Chip to chip variations

Position on ASU

Gain drops along rows 10 % var. between row 1–6 Seen for ASU 14 & 15 so far

chip number

45 50 55 60 65 70 75 80 85 90

gain (DAC/fC)

6.6 6.8 7 7.2 7.4 7.6 Preamplifier gain - ASU 15

Ratio ASU chip/single chip

Normalise measured gain to production gains → attenuation of test Q

chip number

45 50 55 60 65 70 75 80 85 90

gain ratio

0.94 0.96 0.98 1 1.02 1.04 Preamplifier gain ratio PROD/CALIB - ASU 15

6 / 7

Reminder Comparison single chip & ASU chip Chip to chip variations Outlook

Outlook

MICROROCs show great performance: Low noise (0.12 fC) and gain variations of 1 % RMS Channel to channel and chip to chip variations understood as PCB lines variations and attenuation of test signal from interDIF to chips Offset map available for all ASUs Next steps: Complete gain map of all ASU (all data reconstructed) Calibration with Bulk mesh Send jobs on MUST

7 / 7