Design & Development of an Integrated Readout System for Triple-GEM Detectors Alessandro PEZZOTTA III Year PhD Seminar, Cycle XXVIII 22 September s:

Outline Background & Motivation First prototype: GEMMA Second prototype: GEMINI Future perspectives Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"2 22/09/2015

Outline Background & Motivation   First prototype: GEMMA Second prototype: GEMINI Future perspectives Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"3 22/09/2015

Gas-Electron Multiplier (GEM) It belongs to Gas Proportional Chambers family 50 µm-thick Kapton foil with copper clads on each side Perforated by 70 µm-diameter bi-conical channels Immersed into Ar/CO 2 /CF 4 gas mixture (45/15/40) High electric field into channels (10 7 V/m) with a lower bias w.r.t. multiwire chambers Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"4 22/09/2015

Triple-GEM Detector Cascade of three GEM foils Gain Boosted (≈ 10 4 factor) High count-rate (≈ 10 6 cps) Needs dedicated front-end Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"5 22/09/2015

GEM Readout Systems Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"6 22/09/2015 Most of the systems now in use have been re-adapted from other applications: CCDs Semiconductor Detectors Multi-Wire Chambers Not exploiting the full GEM detector potential Uniquely analog or digital systems Limited number of detecting channels included on a single chip

The Main Issue The Pixelated Output It can be adapted according to measurement necessities Variable Pixel Parasitic Capacitance Issues for readout Adaptability Efficiency Speed Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"7 22/09/2015

Outline Background & Motivation First Prototype: GEMMA   Second Prototype: GEMINI Future perspectives Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"8 22/09/2015

First prototype: GEMMA Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"9 22/09/2015 ParameterValue CMOS TechnologySTM 130 nm # of Channels8 Max Pixel Capacitance15 pF Analog OutputsPreamp Analog (selectable) Digital OutputCMOS ToT & Event Detection Max Count Rate4 Mcps Power Consumption3.8 mW/channel Min. Detectable Charge6 fC Sensitivity0.5 mV/fC Dynamic RangeFrom 30 fC to 1 pC Reset ModeDigital

GEMMA Channel Scheme Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"10 22/09/2015

GEMMA Main Blocks Charge-Sensitive Preamplifier Three-Stage NMCFF OTA 90 dB DC-Gain 120 MHz UGBW 100 V/µs SR 6.6 nV/√Hz IRN 1.1 mW Power Comparator Single Ended Mirrored 1.2 mV offset 900 µW Power Log Resistive Ladder DAC 16 Levels (1.53 mV  598 mV) Sets the comparator threshold Ramp Threshold Generator Reference for CTS Comparator Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"11 22/09/2015 Calibration Block for C F cap 5-bit resolution Switched-off during measure 5% Max Capacitance error CTS 7-bit Counter 4 ns Time Resolution (250 MHz) I 2 C Interface Setting the DAC input words Setting the Channel Mode (MIP or Normal) Setting the Ramp Slope Setting Analog Output Signal Logic Control Unit Setting Switch Phases for Reset, MIP and CAL Mode

Charge-Sensitive Preamp 3-Stage Nested Miller FeedForward Compensated Opamp High Gain (90 dB) and PM ≈ 90° 120 MHz Unity-Gain Bandwidth Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"12 22/09/2015

Calibration Circuit Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"13 22/09/2015

Calibration Circuit Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"14 Compensation of CMOS Process and Temperature capacitors variations Automatic procedure 22/09/2015

Calibration Circuit Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"15 How it works 22/09/2015

Charge-Time Converter Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"16 22/09/2015

Comparators Mirrored Opamp Based PMOS Topology for the EDS-Comp NMOS Topology for the CTS-Comp Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"17 22/09/2015

Auto-Zero Circuit Fixes the Comparators switching point and reference voltage Optimizes the switching delay Signal Low-Pass filtering due to switches’ R off Capacitor Divider Losses limited Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"18 22/09/2015

GEMMA Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"19 22/09/ fC Input Charge (MIN)

GEMMA Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"20 22/09/2015 1pC Input Charge (MAX)

GEMMA Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"21 22/09/2015 EDS Delay vs Input Charge vs Pixel Capacitance

GEMMA Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"22 22/09/2015 CTS Duration vs Input Charge vs Pixel Capacitance

GEMMA Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"23 22/09/2015 ENC vs Pixel Capacitance

GEMMA Test Board Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"24 22/09/2015

Outline Background & Motivation First prototype: GEMMA Second prototype: GEMINI   Future perspectives Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"25 22/09/2015

Second prototype: GEMINI Decision to make a second version, GEMINI CMOS technology changed (and related software) to 180nm AMS IBM, more stable and reliable Re-adjustment of specifications Complying with updated detector performance Channel number increased to 16 (instead of 8) LVDS digital outputs and analog output for each channel Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"26 22/09/2015

Updated Requirements Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"27 22/09/2015 ParameterValue Count Rate> 3 Mcps # of Channels16 Min Detectable Charge< 3 fC with Max Pixel Cap OutputAnalog and LVDS Digital Max Digital Output Jitter9 ns Max Pixel Capacitance40 pF Sensitivity1 mV/fC Sensitivity Accuracy5% Reset TriggerEvent-Based

GEMINI Channel Scheme Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"28 22/09/2015

GEMINI Main Blocks Charge-Sensitive Preamplifier Two-Stage Miller OTA 65 dB DC-Gain 320 MHz UGBW 100 V/µs SR 4.3 nV/√Hz IRN 1.5 mW Power Comparator Single Ended Mirrored 0.9 mV offset 700 µW Power R-2R Resistive Ladder DAC 9-bit resolution 500 mV full scale 1.2 mV LSB Sets the comparator threshold, independent for each channel Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"29 22/09/2015 Calibration Block for C F cap 5-bit resolution Switched-off during measurement 5% Max Capacitance error Reset switches High speed Low charge injection Low on-resistance Reset Trigger Constant Event Time Duration Event Triggered External Reset Available I 2 C Interface Setting the DAC input words LVDS Driver

GEMINI CSP Opamp 2-Stage Miller Compensated Opamp Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"30 22/09/2015

GEMINI Comparator Mirrored Topology Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"31 22/09/2015

GEMINI DAC R-2R Ladder DAC, R = 20kΩ Buffered for Threshold Voltage Stability Area/Power Trade-Off Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"32 22/09/2015

GEMINI Layout Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"33 22/09/2015 Area = 6.89 mm 2

GEMINI Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"34 22/09/ fC Input Charge

GEMINI Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"35 22/09/ fC Input charge

GEMINI Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"36 22/09/2015 EDS Delay vs Pixel Capacitance

GEMINI Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"37 22/09/2015 EDS Delay Jitter vs Pixel Capacitance

GEMINI Results Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"38 22/09/2015 ENC vs Pixel Capacitance

GEMINI Boards Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"39 22/09/2015 GEMINI cards GEMINI Test Board

GEMINI Boards Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"40 22/09/2015 GEMINI Readout System

GEMMA vs GEMINI ParameterGEMMAGEMINI CMOS TechnologySTM 130 nmAMS IBM 180 nm # of Channels816 Max Detector Capacitance15 pF40 pF Analog OutputsPreamp Analog (selectable)Preamp Analog (each channel) Digital Output (each channel)CMOS ToT & Event DetectionLVDS Event Detection Max Count Rate4 Mcps5 Mcps Power Consumption3.8 mW/channel2.7 mW/channel Min Detectable Charge6 fC2.5 fC Max Digital Output Jitter18 ns6.2 ns Sensitivity0.5 mV/fC1 mV/fC Dynamic RangeFrom 30 fC to 1 pCFrom 30 fC to 500 fC Input signal common mode900 mV1 V Reset ModeDigitalAuto-Triggered or External Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"41 22/09/2015

Outline Background & Motivation First prototype: GEMMA Second prototype: GEMINI Future perspectives   Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"42 22/09/2015

Future Perspectives Alessandro PEZZOTTA "Design & Development of an Integrated Readout System for Triple-GEM Detectors"43 22/09/2015 Chips Debug Improvement of GEMINI dedicated readout system (Detector Chip Modules and Mother Board) Double the channel per card (32 instead of 16) Setting up an irradiation test to verify rad-hardness