1. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari SSD (Silicon Strip Detector) SDD (Silicon Drift Detector) SPD (Silicon Pixel Detector) Detector Control System for the Silicon Pixel Detector

2. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari 2 layers splitted in 10 sectors each sector carries on 6 staves: 4 outer layer + 2 inner layer each stave splitted in 2 half-stave half-stave basic module

3. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari

4. SPD Basic Building Blocks 32 columns 256 rows Ladder 2: 70.72 mmLadder 1: 70.72 mm Half stave ~193 mm 425  m 50  m Pixel Cell Frontend chip Pixel detector Carrier bus Power supply ~1m 1 data and 2 control links (~200m) PCMCM 16.8 mm 15.86 mm

5. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Electronics System Block Diagram

6. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Services Cooling LV power requirements –LV currents each half stave (@ V ≈ 1.6V nominal) –I analog ≈ 4A, I digital ≈ 3A –Conductor (Cu) width: 2 mm strip on kapton, thickness ≈ 0.20mm ≈ 1.4% X 0 resistance ≈ 40 mOhm –Regulation and filtering of power supplies (space/cooling constraints !) rad-hard linear regulator chip (P. Jarron) at patch-panels filtering with passive components on bus Fibre-optic links 3 (possibly 4) fibres each half-stave single fibre diameter (tight jacket) ≈ 0.9mm, fibre ribbon pitch = 0.25mm

7. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Overview of voltage and current requirements per half-stave Base unit: 1 half-stave = 10 pixel chips SPD (Silicon Pixel Detector) => 120 half-staves Separate analog, digital, detector bias, MCM power supplies Necessary channels: - 120 analog power + ground + sense wires - 120 digital power + ground + sense wires - 120 detector bias + ground - 120 MCM power + ground + sense wires

8. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Possible solutions All power supplies outside the pit distance from detectors => 200 m Power supplies for analog electronics inside the pit distance from detectors => 40 - 50 m Power supplies for digital electronics and detector bias outside the pit distance from detectors => 200 m All power supplies inside the pit distance from detectors => 40 - 50 m

9. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari ALICE Experiment

10. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari The NA57 slow control system (CAEN SY527)

11. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari All power supplies outside the pit (distance from detector => 200 m) - easy to replace the damaged board during the run (not on-board spare channels) - no radiation and magnetic field problems - increased length and cross section of the analog power cables - voltage drop on the analog power cable CAEN SY1527 (for all power supplies) outside the pit Shoebox with capacitive filter 200 m 4 - 5 m SPD analog power digital power detector bias

12. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Analog power supplies inside the pit (distance from detector => 40–50 m); digital and detector bias power supplies outside the pit (distance from detector => 200 m) - spare analog channels => necessary rele’ system - no digital and bias spares CAEN SY1527 (digital power and detector bias) outside the pit CAEN SY1527 (analog power) inside the pit Shoebox with capacitive filter and control logic 4 - 5 m SPD 40 m 200 m

13. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari PIXEL 40-50 m Several cables under test Line impedance adjust: solution under study from CAEN to make use of sense wires or line impedence adjustment

14. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Cost estimate 1st solution (all PS outside) 3 CAEN SY1527 mainframe + 9 A1532 (optional P.S.) 60 KChF 18 + 1 programmable board A1517B (5V/3.6A, 14 ch) 137 KChF 5 + 1 programmable board A1519B (250V/1mA, 28 ch) 48 KChF Cable for digital power (10.5 ChF/m) 42 KChF Cable for detector bias (5.53 ChF/m) 11 KChF Cable for analog power (10.5 ChF/m) 63 KChF TOTAL 360 KChF 2nd solution (analog PS inside and digital PS outside) 4 CAEN SY1527 + 12 A1532 80 KChF 19 + 3 programmable board A1517B (5V/3.6A, 14 ch)159 KChF 4 + 1 programmable board A1519B (250V/1mA, 28 ch) 48 KChF Cable for digital power (10.5 ChF/m) 42 KChF Cable for detector bias (5.53 ChF/m) 11 KChF Cable for analog power (10.5 ChF/m) 10.5 KChF TOTAL 350.5 KChF

15. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Test System for CAEN SY1527 Test System available in Bari Lab: CAEN mainframe SY1527 A1734N board (12 channels, 250 to 6KV, 7mA to 100 mA) Ethernet “TCP/IP” CAEN OPC server installed on pcal04 OPC client via TCP/IP => under study (first tests performed with an OPC client from National Instruments installed on pcal01)

16. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Example of remote monitoring This OPC client from National Instruments runs on a remote workstation (pcal01)

17. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari All power supplies inside the pit (distance from detector => 40-50 m) - reduction cost and length of the conventional analog power cables - reduced voltage drop on the analog power cable - no access during the run - impossible to replace damaged board, necessary spare channels for the analog-digital power supplies and detector bias => notable cost increase Alternative solution --->Adoption of Voltage Regulators with standard powerful power supply Power Supply: ELIND 30KL 38/80 autoranging (0-30 V, 0-80 A) Voltage regulator: L4913 (P. Jarron), others

18. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Solution based on Voltage Regulators

19. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Main parameters of the DCS for the ITS Pixel (1)

20. ALICE DCS Workshop 28/29 May 2001 Vito Manzari, INFN Bari Main parameters of the DCS for the ITS Pixel (2) N.B. All analog channels