1. Multi-Anode ReadOut Chip for MaPMTs: MAROC3 MEASUREMENTS
MAROC3 architecture
Trigger measurements
Charge measurements
Summary
P. Barrillon, S. Blin, C. de La Taille
IN2P3/LAL Orsay,France

2. MAROC2: Experiments and applications
Specifications
Variable gain preamplifier 0-4 to correct PM non uniformity
100% trigger efficiency at 1/3 p.e (= 50fC)
Qmax = 5pC (=30 p.e)
Noise ~ 2fC
Linearity ~ 2%
Cross talk : ~ 1%
Main Application:
ATLAS Luminometer
(absolute measurement of the luminosity)
200 readout chips
Other applications:
ATLAS LUCID: Bologna, 10 chips
Double Chooz: Nevis USA, 150 chips
PET imaging with PMT64: ISS Roma, 30 chips
Tracking detector: Nevod laboratory Russia, 100 chips
Medical imaging with SiPM matrixes: INFN Pisa, 2 test boards
Memphyno Hodoscope: APC, 4 test boards
Roman Pots:
0.5mm2 scintillating fibers
1 Roman Pot = 10*64 fibers in U + 10*64 fibers in V
Multi Anode PM Tubes
64ch Hamamatsu H7546
HV = V
Gain
1-3 non uniformity

3. Sylvie BLIN - blin@lal.in2p3.fr
MAROC 3 – Main Features
Almost pin/pin compatible
Internal reference
Gain adjustement:
8 bits (2,1,…,0.0156) instead of 6 bits (2,1,…,0.0625)
Charge measurement
Variable charge gain
Dynamic range increased
8 or 10 or 12 bits wilkinson ADC
Trigger measurement
Bipolar fast shaper: 2 thresholds
Only 2 DAC
Mux instead of an encoder
2 OR outputs
New digital output levels: Vhigh and Vlow
Mask
Technology: AMS SiGe 0.35 mm
Package: CQFP240
Area: 16 mm2
Power consumption: 220mW (  3.5mW/channel)
30/09/2009
Sylvie BLIN -

4. Fast shaper pedestals Mean=1.926V Rms=1.5mV Mean=1.005V Rms=1.2mV
Noise (mV)
No Cf
Cf = 150 fF
Gain = 1
1.0
0.9
Gain = 64
2.6
1.6
Gain = 128
9.6
4.1
Mean=1.005V
Rms=1.2mV
Noise (mV)
No Cf
C= 20 fF
C= 40fF C=
60 fF
Gain = 1
0.92
0.9
0.89
Gain = 64
3.3
2.75
2.55
2.41
Gain = 128
154
5.57
4.72
4.36

5. 10-bit DAC linearity
DC_FSB
DC_FSU

6. Scurves with FSB1 One channel: Cf=150fF Slope inverse = 2.4V/pC
Intercept ~ 1.920V

7. Scurves with FSU One channel: Cf=60fF Slope inverse = 4.3V/pC
Intercept ~ 0.995V

8. Gain adjustment: scurves with FSB1

9. Gain adjustment: scurves with FSU

10. Trigger Cross talk FSB FSU 50% trigger efficiency Cross talk ch8 47fC
3.1pC
1.5%
ch9
2.9pC
1.6%
FSU
50% trigger efficiency
Cross talk
ch8
48fC
ch7
5.1pC
0.9%
ch9
4.8pC 1%

11. Wilkinson calibration
Tmax (µs)
Vmax (mV)
Data
(adc unit)
Start_counter
(µs)
LSB
(µV/adc unit)
0pC
17.8
164
259
11.325
250
0.1pC
19.6
181
353
10.775
240
0.5pC
26.8
252
639
10.825
243
1pC
34.8
334
957
10.875
247
5pC
74.4
732
2544
10.8
249
10pC 84
826
2930
10.75
50pC
94.4
920
3345
246
Vref_ramp=871mV
Mean start_counter=10.8µs
Vramp at 10.8µs=969mV
Mean LSB=246µV/adc unit
Conversion equation:
V[mV]=data*LSB[mV/adc]+969[mV]

12. Charge measurements: Slow shaper pedestal
Hold2
ADC data
<>= 271 count - s= 1.9 count
=1.036V =0.47mV
DC level
<>= 1.047V - s= 1.6mV

13. Charge measurements: Slow shaper waveforms via wilkinson ADC and linearity
Digital conversion at different hold delay
Slope: adc/pC
Slope: adc/pC
Slope: adc/pC
Gain 4 8 16 32 40 64
Slope
(adc count/pC) 35 70
148
305
383
636
Intercept
(adc count)
271
269
265
262
Fit limit
(pC) 30 20 10 5 3
Hold delay : 85ns

14. Summary MAROC3 Third version of MAROC has showed nice performances
Test board:
Sophia-Antipolis Géosciences Azur : Geoscience tomography with cosmic muons, Micromegas-bulk, 54 chips
University of new Hampshire: Positron Resolution in Lanthanum Bromide Scintillators using MaPMT
CSNSM: Gamma-ray localization in a monolithic LaBr3 scintillator
Available chips: 1250 chips
MAROC3
inputs
number 64
polarity
negative
outputs
triggers
64 triggers
charge
1 analog multiplex
1 digital charge (12, 10 or 8 bits) PA
Gain variable
8 bits
(0 to ~4)
BFS
Gain
4.5V/pC
Noise
1.6mV
Min charge
5fC
UFS
2.3V/pC
2.4mV
3fC
Slow shaper
156.7mV/pC (gain64) – 4pC
0.53mV