Transcript Santiard
ANALOG AND DIGITAL PROCESSING FOR THE READOUT OF RADIATION DETECTORS J.C. Santiard, CERN, Geneva, CH ([email protected]) K. Marent, IMEC vzw, 3001 Leuven, BE ([email protected]) H. Witters, IMEC vzw, 3001 Leuven, BE ([email protected]) J. Hauser, CMS UCLA Sh. Chandramouly, CMS UCLA J.C Santiard CERN EP-MIC CERN EP-MIC LONG P.T. ANALOG FRONT-END DEVELOPMENT Long peaking-time(.5 s; 1.2 s) used as delay, waiting for a trigger to memorize on cap. by T/H; multiplexed output. General use 1987 AMPLEX 3m tech. 60 wafers 1990 AMPLEX-SICAL 3m tech. 100 wafers Gaseous detectors 1993 GASPLEX 1.5m tech. 10 wafers 1994 GASSIPLEX1.5 1.5m tech. (Si) 60 wafers 1998 GASSIPLEX0.7 0.7m tech. (Si) Proto. J.C Santiard CERN EP-MIC SIGNAL PROCESSING FOR GASEOUS DETECTORS Ions drift time of several tens of s from anode to cathode: i(t) = I0B/(1 + t/t0) q(t) = Q0ALn (1 + t/t0) A, B and t0 are constants depending on detector geometry and electric field. Filtering adaptable to any kind of drift time J.C Santiard CERN EP-MIC CONTINUOUS TIME DECONVOLUTION FILTER GOAL: RECREATE A STEP FUNCTION FROM THE LOGARITHMIC SHAPE OF THE CHARGE OR A DIRAC PULSE FROM THE CURRENT SIGNAL. Impulse response of detector model with Dirac input: h(t) = U(t)/(t0+t) U(t) is a step function function of the deconvolver G(s) should be: G(s) = H(s)-1 H(s) = L[ h(t) ] 3 exponentials in the feedback of a summing amplifier: G(s) = Vout/Vin = A/(1 + A) ; if A>>, G(s) ~ 1/ J.C Santiard CERN EP-MIC PRACTICAL IMPLEMENTATION 3 weighted exponential: = K1/(1 + sT1) + K2/(1 + sT2) + K3/(1 + sT3) Gain factors: K1 = 0.2; K2 = 0.3; K3 = 0.5 Time constants: T1 = C1/gm1 ; T2 = C2/gm2 ; T3 = C3/gm3 J.C Santiard CERN EP-MIC ACTIVE FEEDBACK RESISTOR Rf = 20 M J.C Santiard CERN EP-MIC POLE/ZERO CANCEL. RESISTOR Rp/z = 2.2 M J.C Santiard CERN EP-MIC SHAPER NO DIFFERENTIATING CAPACITOR J.C Santiard CERN EP-MIC SIMULATIONS RESULTS CSA OUTPUT FILTER OUTPUT SHAPER OUTPUT J.C Santiard CERN EP-MIC LAYOUT J.C Santiard CERN EP-MIC MEASUREMENTS NOISE Vs Cin GAIN SPREAD 40 30 1800 1600 1400 1200 1000 800 600 400 200 0 Channels y = 11.262x + 470.16 25 20 15 10 5 Cin mv/fC J.C Santiard CERN EP-MIC 3. 8 3. 75 100 3. 7 50 3. 65 0 3. 6 0 3. 5 e- rms 35 LINEARITY 2000 3 y = 3.5329x + 5.2869 2 OUT errors fC OUT mv 1500 1000 500 1 0 -1 0 200 400 -2 0 0 200 400 600 -3 IN fC IN fC J.C Santiard CERN EP-MIC 600 7 6 5 4 3 2 1 0 4.4 4.2 Gain (mV/fC) OUT fC CALIBRATION 4 3.8 3.6 3.4 3.2 3 0 5 10 15 0 5 10 Channel Number CHANNEL J.C Santiard CERN EP-MIC 15 SHAPING ON GASEOUS DETECTOR PAD WITH 55Fe Xray SOURCE J.C Santiard CERN EP-MIC TABLE OF RESULTS(1) Technology Silicon area Silicon detector mode Gain Dynamic range ( + ) Dynamic range ( - ) Non linearity Noise at 0 pF Noise slope Low power mode Power consumption Noise at 0 pF Noise slope MIETEC-0.7m 3.63 x 4 = 14.5 mm2 2.2 mV/fC 900 fC ( 0 to 2 V) 500 fC ( 0 to -1.1 V) 3 fC 600 e- rms 12 e- rms/pF 4mW/chan. at 4 MHz 600 e- rms 15 e- rms/pF J.C Santiard CERN EP-MIC TABLE OF RESULTS(2) Gaseous detector mode Peaking time Peaking time adjust. Noise at 0 pF Noise slope Dynamic range ( + ) Dynamic range ( - ) Gain Non linearity Baseline recovery Analog readout speed Power consumption Out. Temp. coeff. 1.2 s 1.1 to 1.3 s 530 e- rms 11.2 e- rms/pF 560 fC ( 0 to 2 V ) 300 fC ( 0 to -1.1 V ) 3.6 mV/fC 2 fC .5% after 5 s 10MHz (50 pF load) 8mW/chan. at 10 MHz 0.05 mV/0C J.C Santiard CERN EP-MIC BLOCK DIAGRAM J.C Santiard CERN EP-MIC DILOGIC2: A SPARSE DATA SCAN READOUT PROCESSOR CHARACTERISTICS: 16 TO 64 CHANNELS PED. SUBTRACTION ZERO SUPPRESSION 512X18 BITS DATA FIFO 64X16 BITS BITMAP FIFO 4 BITS CONTROLLER ASYNCHRONOUS R/W FIFO FLAGS PROTOTYPES DELIVERY: OCT. 99 J.C Santiard CERN EP-MIC 16-Ch. LCT-COMP USE ON THE CSC ENDCAP MUON DETECTORS IN CMS TO LOCALIZE THE TRACK HIT POSITION TO 1/2 STRIP. COMPARATORS HAVE LOW OFFSET SPREAD: <.9mv rms. SPATIAL RESOLUTION DEPEND MAINLY ON THE INPUT NOISE LEVEL. ON-CHAMBER TESTING WILL BE DONE DURING SUM. 00 PRE-PRODUCTION WILL START IN MARCH 00 J.C Santiard CERN EP-MIC