CARDIAC meeting – 30 Sept 05 M3R3-M5R3-M5R4 FEE status

CARDIAC meeting – 30 Sept 05 2 Overview  FEE – from ASDQ to CARDIAC ASDQ++ CARDIAC I2C induced signals  HV induced noise HV noise coupling  LV distribution Regulator Vout spread & LV distribution bars Vdrop  CARDIAC threshold scan M3R3 – M5R3 – M5R4  Grounding Detector grounding scheme  Conclusions

CARDIAC meeting – 30 Sept 05 3 ASDQ++ A brief history (I) Nightmare  first two chambers prototypes test  fee instability  cable layout/orientation sensitivity ASDQ++ PCB rel. 2  small improvement on the instability side  still problems with cabling Buffer board & FC connections  fully stable fee behavior  no dependency on cable layout - Some capacitors for supply voltage decoupling - inner layers for GND/V+/V-

CARDIAC meeting – 30 Sept 05 4 ASDQ++ A brief history (II) Programmable current sink ASDQ output stage  standard current set : 3 mA (300 mV/100 )  current set for driver board : 1 mA (300 mV/300 ) R=300  SPB ASDQ++ Ground connection Faraday cage HV 1 M  680 nF Faraday Cage sensitive path Cathode pads readout LVDS

CARDIAC meeting – 30 Sept 05 5 ASDQ++ A brief history (III) Pads X-talk  charge injection in pads belonging to the same pad wire  charge injection in contiguous pad wires HV Signal on this wire pad Signal injection charge injection in pads belonging to the same pad wire  poor ground connection (capacitor-GND) charge injection in contiguous pad wires  nose ground not enough  a resistor in the grounding path mitigates the problem and help with HV & pickup noise Z GND < Z Wire Pads HV nose

CARDIAC meeting – 30 Sept 05 6 The IB System architecture The IB and the TB boards HV Signal on this wire pad Signal injection Z GND << Z Wire Pads HV nose 22  In the last T11 TB 4 CARIOCA (NOT CARDIAC !!!) boards were installed in one of our M3R3 chamber. We took some V th  6/7 fC

CARDIAC meeting – 30 Sept 05 7 CARDIAC I2C induced signals (I) I2C A B C D E F Termination

CARDIAC meeting – 30 Sept 05 8 CARDIAC I2C induced signals (II) Read Scaler Read all registers M3R3 CARDIAC : A – B – C – D [all channels] M3R3 CARDIAC : F [1° (?) channel – other channels ok] Read all registers Read Scaler NB : 5 pulses are generated by the readout procedure (?!) ask to Valerio CASINO ? I2C CARDIAC out I2C CARDIAC out I2C CARDIAC out

CARDIAC meeting – 30 Sept 05 9 CARDIAC I2C induced signals (III) I2C A B C D E F Termination All boards/all channels OK Problems in the PCB due to high frequency signal components CARDIAC F – 1° channel

CARDIAC meeting – 30 Sept CARDIAC I2C induced signals (IV) Termination I2C A B C D E F No ch1 problem with M5R3 chamber ??!! M3R3 – M5R3 difference : C pad value M5R3 C pad I2C line Z1Z1 Z2Z2 I1I1 I2I2 CARIOCA C parasitic What are we going to have with smaller C pad and shorter interconnection cables ?

CARDIAC meeting – 30 Sept HV induced noise Noise coupling Continuous cathode Wire Cathodes HV distribution line = antenna I noise filter HV before distribution line 6 cm  V < 5 V C = 2.2 nF

CARDIAC meeting – 30 Sept LV distribution Regulator output voltage spread I load =1.5A 60 mm LV distribution bars - PCB dimension for region R4 800 mm R=0.45 m/□  R = (800/30)*0.45 m  Voltage drop ~ 20mV (< 1% Vcc) GND VCC

CARDIAC meeting – 30 Sept CARDIAC threshold scan M3R3 – M5R3 – M5R4  M3R fC (working threshold = 5 fC)  M5R fC (working threshold = 5 fC)  M5R fC (working threshold = 10 fC) HV ON

CARDIAC meeting – 30 Sept Grounding Detector grounding scheme  No current through the reference GND  Reference GND = Safety GND  3 A fuses on the LV distribution system  1 mA max current on the HV lines  Low step up current in case of failure  No current through the reference GND  Reference GND = Safety GND  3 A fuses on the LV distribution system  1 mA max current on the HV lines  Low step up current in case of failure system reference ground safety ground

CARDIAC meeting – 30 Sept System qualification Skew measurements  M4(M5)R3  To verify front-end behavior threshold scan should be executed WITHOUT HV ON (HV is a source of external noise and can be filtered out), anyway FEE work fine with the 3 instrumented chambers  No instability due to cable layout or external source has been detected  HV filters are OK with the HV PS we have used in our test, but that PS is not the final one !  LV boards and LV distribution are OK (~10 mV drop for M3R3 regions and ~20 mV for M4R4 regions)  The detector grounding scheme has already been (successfully) reviewed  The 3 instrumented chambers work fine (NB : M5R3 is not instrumented with the final FC)  I2C access can trigger CARDIAC output spurious pulses ONLY during CARDIAC access According to our tests CARDIAC work fine when used to instrument M3R3, M5R3 and M5R4 chambers