AHCAL Electromechanical Integration M Reinecke EUDET annual meeting

AHCAL – Electromechanical Integration M. Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

Outline -AHCAL - Mechanical and Electrical Integration -Light Calibration System – First Results -Integration Studies Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

AHCAL Half Sector - Integration AHCAL Slab 6 HBUs in a row HBU HCAL Base Unit typ. 12 x 12 tiles SPIROC typ. 4 on a HBU HEB HCAL Endcap Board Hosts mezzanine modules: DIF, CALIB and POWER HLD HCAL Layer Distributor Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

Mechanical Constraints Requirements for a HCAL Base-Unit (HBU) from the Barrel‘s mechanics: -As large as possible (assembly time) -As thin as possible (barrel diameter) -Easy de-/installation of single units (repair) HCAL: 2 x 8 Sectors 2, 432, 000 Tiles -Rail System needed (Sector walls ? ) -Minimize dead area Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

HBU – Cross Section Reflector Foil Polyimide Foil HBU Interface 100µm 500µm gap ASIC PCB Sector Spacer TQFP-100 800µm UV LED Top Plate wall 500µm 1. 7 mm 1 mm high fixing Component Area: Si. PM 900µm high Bottom Plate Tile HBU height: 600µm 3 mm 6. 1 mm (4. 9 mm without covers => absorber) Mathias Reinecke Bolt with inner Absorber M 3 thread Plates welded to bottom (steel) plate EUDET annual meeting – Paris 8. -10. Oct. 2007

HBU – PCB Layer Structure -6 layer design with cut-outs for ASICS and connectors -75 W Lines for high-gain Si. PM setup -Two signal layers for impedance-controlled routing -Total height (PCB + components): 1. 5 mm -Two companies agreed on structure at reasonable costs!! Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

Ligth Calibration System (LCS) Si. PM response strongly depends on temperature and bias voltage. LCS (based on UV LEDs) needed for: -Calibration (ADC counts per PE) -Gain Monitoring Two different concepts under investigation: - Quasi-Resonant LED driver setup on DIF, fibers into AHCAL gaps (see: our Prague colleagues, I. Polak et al. ) - One LED per tile, direct coupling without fibers (currently tested at DESY) Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

LED Testboard (LCS Test) Test LED integration into HBU (LCS): -Crosstalk of driving circuit to Si. PM? -Integration to PCB / coupling to tile? -Connector test: stability, number of connection-cycles? Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

LED Integration LEDs radiate through holes in PCB 1 Cent Two different types of LEDs assembled on PCB (top) Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

LED optical output Pulse Generator Output (inv), 2. 5 V pre-bias of LED 5 ns 30 n. W peak LED optical output, measured with PMT H 9858 -01 (Hamamatsu) in 50 W, Vc=0. 8 V => Gain ≈ 3*10^(4) A/W Our LEDs are very fast !!! Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

LED driving circuit on HBU LED: Ledtronics SML 0603 -395 -TR Transistor: Infineon BFR 340 F (npn) Mathias Reinecke EUDET annual meeting – Paris Charge on Cdrive defines current through LED 8. -10. Oct. 2007

Response from Tiles Trigger Si. PM 1 WLS decay time? 30 ns Si. PM 2 Si. PM 4 Only LED 1 active Mathias Reinecke Si. PMs coupled to oscilloscope (50 W), LED 1 amplitude controlled by VCALIB(DC). EUDET annual meeting – Paris 8. -10. Oct. 2007

Estimate Crosstalk Scope in averaging mode Light in Tile 1 ≈40 m. V Crosstalk to tile 2 and tile 4 ≈1 m. V Crosstalk ≈ 2. 5% electr. /optical ? ? Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

LCS Status y r GOOD - The LEDs can be assembled automatically without problems. All of the 5 tested LEDs survived the assembling. -The LEDs are very fast. -The driving circuit works concerning speed and amplitude. The amplitude can be controlled in wide range by VCALIB (6 -9 V) m li a in e r P Critical -The driving voltage (base of transistor) has to be large (1 V step). -The sensitivity to changes of the driving amplitude is high. Next steps -Connect the LED testboard to the ASIC‘s testboard (VFE ASIC) in order to measure dynamic range, crosstalk and linearity w. r. to VCALIB and LED uniformity. Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

Testboard II : ASIC + Integration SPIROC Testboard (HBU prototype): -Assembly (Tiles, PCB, ASICs, LEDs), Cassette Construction -Performance in the dense HBU setup: Noise, gain, crosstalk, power and signal integrity -DAQ Interface -LCS with LEDs on board. Tile integration to HBU : see M. Danilov‘s talk (alignment pins) Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007

Testboard III : Power-System Test Power-Ground System (2. 20 m): -Oscillations when switching? -Voltage drop, signal integrity (traces, connectors)? -SPIROC performance @ far end (blocking caps sufficient)? ‚Layer Concentrator‘ (DIF*) Extenders (Power-Gnd, Traces) Mathias Reinecke EUDET annual meeting – Paris SPIROC Testboard 8. -10. Oct. 2007

Conclusions -First ideas about the next generation AHCAL develop to a promising concept. -Feasibility of many design aspects (e. g. PCB structure) have to be proved. -Testboard Design I (LCS) is alive now! -Testboard II (HBU prototype) design starts in spring 2008. -Testboard III (power plane test) runs in parallel (beginning of 2008). -Mechanical engineering of absorber stack and HBU cassette is starting! Mathias Reinecke EUDET annual meeting – Paris 8. -10. Oct. 2007