AGATA CORE & GROUNDING

• AGATA Triple_Cryostat Core_SegmentsSignals & Pulser wirering & return GND

• Analog_Digital GND_Plane Regions& Grounding of Mixed Signals PCBs!

• “IDSS” LV-PS, HV-PS (new design)• Mechanical Design _ AGATA

DEMONSTRATOR GROUNDING - GND Plate_Structure,- GND_Frame_Structure (if any?)- Cable Channels (length, 5 or 10m?)

-presented by G. Pascovici Padova, Sept. 22-23, 2005

AGATA_Demonstrator ( 5 x TC)_Grounding

• Capsule & Cold Parts GND 0!• Triple Cryostat GND 1• LV-PS (PS_1) one / TC GND 2• FADC-PS (PS_2) GND 3• SLOW_CNTRL_PS (PS_3) GND 4• HV_PS (15x HV + CNTRL) GND 5

• the “IDSS”_GND [ GND 2;3;4] & [1,5] !

• Very good Filtered LV_PS & HV_PS & PS3 !!• Very Solid SYSTEM_GND and very Solid

Connections to the AGATA_DEMO._GND !!( PS_1 & 2 & 3) !!

• Solid_Meshing_like Architecture for AGATA_GND decided (GSI, Feb.2005)

N.B. The differential transmission line does not improve the S/N ratio at the detector/cryostat place!

- only minimizing radiated electromagneticinterference (EMI) !

- 80µV ~ 1.5 * CW / 14bit_ADCor ~ 6*ADC_CW / 16 bit_ADC

AGATA test cryostat for single detectors*

* D.Weisshaar, GSI, Feb. 2005

Position of cold preamps for nearest neighbours event *

* D.Weisshaar, GSI, Feb. 2005

Triple Cryostat Wirering_Grouding

Problems:twisted Signal_GND?!

- now only for Core!- Segments return

GND ?! - GND one_both ends ?!thermal shunt limitationspulser wirering ?

Connector problems:- only MicroMatch(20)?! - formerly also MDR-26

HP-Ge - Detectorthermal stress ?!

- GND_0 Cold part

- GND_1 Warm PartD1 D2 D3CB CB

CS CF

RF

CF CF

RF RF

CD

CS

CC

VACUUM

x36 x3 x36

1.8Ω

cold part

6x TRIPLE CORE + PULSER 6x TRIPLESEGMENTS SEGMENTS

Ro [GND0 <-> GND1]

Al

GND1

GND1

~8cm~8cm

GND0

GND0

GND1MDR(26)

PTFE ~8cm

~12-15cm~12-15cm

MDR(26)MDR(26) GND1GND1

~8cm~8cm

MicroMatch (20)

MicroMatch (18)MicroMatch (18) MicroMatch (18)

MicroMatch (20) MicroMatch (20)

LN2 - DEWAR Al

CTT Feed through

PULSER @ Core & Segments

Pulser tr ~ 10 ns

core

segment

Pulser tr ~ 100 ns

core

segment

Problems:- we have to understand the

equivalent “transfer function” of the pulser signal (for core and segment) !- tr segments ~ 25 ns @ ~15-20 pF- tr core ~ 29 ns @ ~ 45 pF- pulser energy resolution ~ 1.25 keV- core / segments ration ~ 20 (24) Pulser tr ~ 250 ns

core

segment

AGATA Detector CSP_Set ( 12 Segments + 1 Core)

- a new solid GND concept for the set of

(12+1 )_CSPs/ Agata_Detector

-Gnd

Layer

-the GND_Layer

-the Top_Layer

ATLAS / AGATA Grounding &Differential Transmission Line

• MDR Cable Specs.grounded on both sides !

• Fully Differential !terminated 100 Ohm!

• the S/N ratio_ (A)/(B) ?!(length 5-10m?)

• Impedance Z =

100 Ohm +/- 10%

• Transmitter:50 Ohm decided

• Receiver: 100 Ohm !

• A_GND / D_GND ? NO !

o

http://bmc.bu.edu/bmc/faraday/atlas_gn.pdf( )

(A) (B)

AGATAATLAS

AGATA Triple_Cryostat equipped with Triple_Segment & Core_Pulser CSPs Power Supply Signals & Analog GND

- „MDR“ 26-via Male Connector(see also A. Pullia et al „Agata Hybrid

Preamplifier-White Paper § Cable & Interface, 2005)

- LV_PS D-SUB 25Pin Assignment to be decided !!Res. 8 V (?) for higher dynamic range

(or – 6 V Sense ) decidedRes. 8 V (?) for higher dynamic range

(or + 6V Sense ) decided

- 3 x 6 „MDR“ male connectors for the Segment_ CSPs

– 3 x 1 „MDR“ male connectors for theCore&Pulser_CSP

( NO PS_WIRES to FADC !! )– 1 x 25 D-SUB connector for the

Triple_Cryostat_PS decided !( Cologne, Sept. 2005)

AGATA_Triple_Cryostat HV_PS CNRTL Signals

- HV-PS CNTRL lines ( IDSS_ to be decided )- V (set) (0 to 2.5V / 1kOhm) & slope of (1-10 V/s) ??- V(mon) (0 to 2.5V / 10kOhm) corresponding to (0 to 5 kV_HVout)- I(mon) (0 to 2.5 V/ 10kOhm) corresponding to (0 to 1µA_HV_Iout)

-HV_PS D_SUB_15(male) for HV_PS CNTRL (??)Pins 1; 6 & 11 +5V for D1/D2/D3 respectivelyPins 2;7 &12 V(set) dittoPins 3;8 & 13 GND common GND for D1/D2/D3Pins 4;9 & 14 V(mon) dittoPins 5;10 & 15 I(mon) ditto

– 3 x HV_PS- (D1/ D2 /D3 Individual HV_PS)

(ISEG_MHP 50-103-2.5)- +/- 5 kV (max); - I (out) 0 to 10 µA;- V (set) 0 to 2.5V; - V(U_mon.) 0 to 2.5V- V(I_mon.) 0 to 2.5V

Specifications- Stability less then 10(-4) / R load & U(in)- Temp. Stab. less then 5.10(-5)/ grad C- Mechanical: 80 x 40 x 14 [mm]

AGATA_Triple LN2 Level Capacitive-Preamplifier

Specifications:

• capacitive measurement (very low noise)power consumption less then 25 mW

• D_SUB 15 female connector for LN2_Level • Pin allocation proposal has to be decided !

- Pins 1;2, 3;4, 6;7, 8;9 reserved for PT_100- Pins 11;12 LV_PS (+/-12V)- Pins 13;14 Dif. Output (Linear 0-10V/1 kOhm)- Pins 5;10 Analog_GND (Detector GND)!

(see also G.Pascovici et al. AGATA LN2 Level _Capacitive Preamplifier)

– LN2 Level monitor– signal internally, triangular ~1kHz– cable twisted shielded– (opt. additionally 2x PT_100 with 4 outs)– LV_PS ( +/- 12 V) and Analog_GND (only)!– Enable/Disable LN2 Cap_Mon. (Opt.)!

AGATA LN2 Level / Capacitive Preamplifier

U out [V]

C d[pF] LN2 [cm]

First measurements with AGATA-Triple Segment and Core_Pulser Preamplifiers

– Specifications:

• AGATA Hybrid Preamplifiers with Pulser(Draft version 1.4-June 2004) by A.Pullia)

First results presented at IEEE

Nuclear Science Symposium, Roma, 2004.

• “The AGATA charge-sensitive preamplifiers with buil-in pulser and active-reset device”

• by A.Pullia, G.Pascovici, B.Cahan, D.Weisshaar, C.Boiano, R.Bassini, M.Petcu, F.Zocca

Wirering & Grounding Problems

• IN2P3_Ganil CSP - INFN_Milano – Segment CSPs- C(v) frequency compensation Low Drop

Regler_PS requests Rs, stronger HF filter and exact values of LV_PS ( mainly for +/- 6V ) to solve that sense wires needed IDSS @ LV_PS design.

• IKP Cologne - Core CSP & Pulser- C(v) frequency compensation PS_ Grounding

(Motherboard)

• Pulser amplitude ratio Core/Segments about 20 (25), i.e. for an equivalent ~10 MeV in core one get ~ 400 keV in segments

CSPs for the first AGATA_Detector Core TestSpecification IKP-Cologne

(a) (FET_BF862)

IKP-Cologne(b) (FET_IF1320)

IKP-Cologne(Miniball) (FET_IF1320)

Sensitivity( mV / MeV )

~ 100 mV/MeV( differential )

~ 100 mV/MeV( differential )

~ 175 mV/MeV( single ended )

Resolution(Cd= 0pF; cold FET) ~ 600 eV ~ 600 eV ~ 600 eV

Slope( + eV/ pF) [Cd]

< 10 eV / pF(cold FET)

< 10 eV / pF(cold FET)

< 10 eV / pF(cold FET)

Rise time (Cd= 0pF)

< 12 ns( warm FET)

~ 15 ns( cold FET)

~ 15 ns( cold FET)

Slope( + ns/ pF) [Cd]

~ 0.25 ns( < 22 ns / 45 pF )

~ 0.3 ns( ~ 29 ns / 45 pF )

~ 0.3 ns( ~ 25 ns / 33 pF )

U(out) @ [100 Ohm] /Power [mW]

~ 2.0V*/ ~290 mW(LM-6171; AD-8057)

~ 2.0V*/~ 290 mW(AD-8057;AD-8012)

~ 4.5V*/~ 450 mW( + /- 12V) (LM-6172)

Charge Sensitive Stage Saturation

equiv. 90 MeV equiv. 100 MeV equiv. 100 MeV

Open Loop Gain(calc.)

> 100,000 ~ 20,000 ~ 20,000

AGATA CORE & PULSER

0

1000

2000

3000

4000

5000

0

1000

2000

3000

4000

5000

1200 13001170 1250 1340

keV

70006200 6400 6600 6800

Chn

Agata_Core_SlowUndGen_Zoom.spc

Co60

60Co

Pulser

Co 60~ 2.15 / 2.26keV

Pulser ~ 1.25 keV

AGATA Core & Pulser

0

1000

200

400

600

800

0

1000

200

400

600

800

10050 60 70 80 90 110 120 130 140

keV

2000 30001500 2500 3500

Chn

Agata_Core_SlowAmCoGen6_Zoom.spc

Am

Co

Co57

57

Pulser

241Am

241 ~ 1.25 keV

Pulser ~ 1.25 keV

AGATA Core Preamplifier

Core Pulser

AGATA_Grounding of Mixed Signals PCBs• IEEE [ H_Ott_Consultants] Golden Rules:

• a single GND Plane but

- partitioned into Analog & Digital sections

- strict discipline of routing only

through bridge !!

• ADC manufacturer „GND_Guru“:„ a) the A_GND and D_GND must be connected together externally to the same low impedance GND_Plane with minimum lead length.

b) any extra external impedance in the D_GND connections will couple more digital noise into analog circuit through the stray capacitance to the IC (ADC)“

N.B. .. For single ADC PCB only!

http://www.hottconsultants.com/outlines/mixed_signal.html

( ))http://www.hottconsultants.com/techtips/tips-slots.html

( )

Separate Analog & Digital GND_ Plane Regions

„H.Ott „techtips“ :

- Separate Analog & Digital GND. Plane Regions as an Additional Solution for Noise Isolation for High Resolution fast ADCs ( e.g. 14 bit / 1V pipe line ADCs)

-the GND plane is NOT really split it is only properly partitioned !!

- NO traces, on any layer, can cross over the isolating slots in the GND_Plane!!

- all traces cross only the

„ADC_bridge_point“

http://www.hottconsultants.com/outlines/mixed_signal.html( )

http://www.hottconsultants.com/techtips/split-gnd-plane.html( )

AGATA_Grounding Main References(A) Noise and Grounding Books & “White_Papers”.

• (1) H.W. Ott, "Noise Reduction Techniques in Electronic Systems,"2nd Edition, by publisher: John Wiley & Sons, 1988, ISBN#: 0-471-85068-3... ["The IEEE Bible on EMC" ]

• (2) John R. Barnes, Electronic System Design: Interference and Noise Control Techniques, New Jersey, Pretice-Hall, Inc.,1987

• (3) Morrison, R., Lewis, W. H., Grounding and Shielding in Facilities, John Wiley, 1990 • (4) Alain Charoy, Compatibilité Electro-Magnetique (DUNOD),Paris, 2000, ISBN 2 10

004209 2

• http://alicedcs.web.cern.ch/AliceDCS/ElectrCoord/Documents/ALICE_GndPlan_draft_190602.pdf

• http://alicedcs.web.cern.ch/AliceDCS/ElectrCoord/Slides/Forum20020320-Stefanini.pdf• http://atlas.web.cern.ch/Atlas/GROUPS/FRONTEND/WWW/atlas_gn.pdf• http://bmc.bu.edu/bmc/faraday/mdt_gnd.pdf• http://www.ikf.physik.uni-frankfurt.de/~renfordt/ALICE/LV/tpc_grounding_v1.0.pdf

(B) AGATA Analog Front_End Electronics, FADC and IDDS grounding conceptual design.

• (11) D. Weisshaar AGATA Detector&Cryostat Conceptual Design• (12) A. Pullia AGATA Hybrid Preamplifiers with Pulser (Draft version 6-3,Sept. 2005) • (13) P. Medina AGATA FADC Conceptual Design • (14) I. Kojouharov, J.Gerl AGATA IDDS Conceptual Design

AGATA_Grounding “ADC_Guru” References for single ADC and single PCB

• http://www.analog.com/IST/SelectionTable/?selection_table_id=204• http://www.analog.com/UploadedFiles/Data_Sheets/394593663940380402103990

61519954AD6645_b_.pdf•• http://focus.ti.com/lit/ds/symlink/ads5500.pdf• http://www.ti.com/corp/docs/landing/ads5500/ads5500evm_diffampusrguide.pdf• http://focus.ti.com/lit/ug/slwu010a/slwu010a.pdf• http://www.linear.com/pc/downloadDocument.do;jsessionid=CXlyDGtwnO8fBQr7fz

J29uTumOs2OuewUsaUe2taSNCWNTNFNLXm!-1708105310?navId=H0,C1,C1155,C1001,C1150,P9250,D6617

• http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1155,D4160• http://www.linear-

tech.com/pc/downloadDocument.do?navId=H0,C1,C1155,C1001,C1150,D4160• http://www.linear-

tech.com/pc/downloadDocument.do?navId=H0,C1,C1155,C1001,C1150,P7598,D5234

• http://www.datel.com/data/ads/adc-an1.pdf• http://archive.chipcenter.com/analog/tn024.htm

About Henry W. Ott: ReferencesHenry W. Ott: Noise Reduction Techniques in

Electronic Systems,"2nd Edition, publisher: John Wiley & Sons, 1988, ISBN#: 0-471-85068-3.

• Henry Ott Consultants:Electromagnetic Compatibility Consulting

&Training• http://www.hottconsultants.com/outlines/mixed_signal.html• http://www.hottconsultants.com/pdf_files/june2001pcd_mixeds

ignal.pdf• http://www.hottconsultants.com/pdf_files/Antennas.pdf• http://www.hottconsultants.com/techtips/split-gnd-plane.html• http://www.hottconsultants.com/techtips/tips-slots.html