1 / 24

FAZIA

FAZIA. WG3 – Front End Electronics. Digital Electronics. Dual channel preamplifier Simultaneous charge and current outputs Charge: energy and timing information High speed, High resolution digitization (100 Ms/s 14 bit) Energy extraction through digital shaping

alaura
Download Presentation

FAZIA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. FAZIA WG3 – Front End Electronics WG3 - Pierre Edelbruck

  2. Digital Electronics • Dual channel preamplifier • Simultaneous charge and current outputs • Charge: energy and timing information • High speed, High resolution digitization (100 Ms/s 14 bit) • Energy extraction through digital shaping • Timing extraction through pulse shape analysis • Digital trigger • Current: pulse shape analysis • Ultra High speed digitization (2 Gs/s) WG3 - Pierre Edelbruck

  3. Channel structure WG3 - Pierre Edelbruck

  4. Digital Electronics • Advantages: • High flexibility through VHDL / Software programming • Possible sophisticated trigger algorithms • “Pretrigger” capability: past information still available after trigger • Reduced or no dead time • Hardware • ADC Linear Technology LTC 2254 (100 MHz, 200 MHz available) • FPGA Xilinx - Spartan III • Up to 5 Million gates • Embedded memory (1872 kbit = 100 kword = 1000 µs @ 100 MHz) • Arithmetics • DSP ADSP-2191 (single chip 16 bit) • Analog pipeline:1236 samples, 2 Gs/s, readout @ 50 Ms/s (25 µs) WG3 - Pierre Edelbruck

  5. Project Status • 2 prototypes built in 2005-2006 • Jointed development in Florence and Orsay • VHDL and software • VHDL • Interfaces with DSP, VME, stand alone USB • Handling of the Analog Pipeline • Various housekeeping tasks: offset compensation etc. • Storage and readout of both charge and current waveforms • Hardware, continuous, trapezoidal shaping • Fast trigger with fast trapezoidal filter • High speed analog inspection line (100 Ms/s DAC) WG3 - Pierre Edelbruck

  6. Project Status • Software • Stand alone development bench (USB-Labview) • Noise evaluation module (ENOB calculation) • Calibration of the analog pipeline • Hardware for the Legnaro experiment • VME carrier boards • 8 FEE boards, revised PCB • PACI with patch panels WG3 - Pierre Edelbruck

  7. WG3 - Pierre Edelbruck

  8. WG3 - Pierre Edelbruck

  9. WG3 - Pierre Edelbruck

  10. WG3 - Pierre Edelbruck

  11. Trigger WG3 - Pierre Edelbruck

  12. Energy shaper WG3 - Pierre Edelbruck

  13. Global System Architecture • 1 telescope = 2 Si + 1 CsI (photodiode) • Single telescope area = 20 x 20 mm2 • Coverage = 4  • If Rdetector = 1000 mm  31 000 telescopes • If Rdetector = 500 mm  7 800 telescopes  15 600 preamp (if no PD)  31 200 analog channels WG3 - Pierre Edelbruck

  14. System architecture • Massive channel count requires (some) organisation • Tree structure proposed • Bottom level = detector with front end electronics • Intermediate level = regional : gather FEE information • Top level = DAQ & global trigger • Objective: • Reduction of the connection count Closer to the top of the hierarchy = less wires ! • Possibly push the entire bottom level INSIDE the vacuum chamber • Positive side effect: • Very short analog path from PA to ADC WG3 - Pierre Edelbruck

  15. System Architecture DAQ + Global trigger 1 Regional level Data & trigger processing 100 regional boards 1000 FEE FEE PACI Detector level 10000 telescopes WG3 - Pierre Edelbruck

  16. Module for 4 telescopes WG3 - Pierre Edelbruck

  17. Issues • A few issues to work on … • High power to be evacuated through conductive heat sink • Any decision about neutrons ? • Data and trigger path to be designed • Can we design a hierarchical trigger system ? • Nota bene • The thermal issue is critical and requires a careful design • Wiring issues will have to be solved anyhow • 30 000 coaxial cables are not transparent to neutrons either WG3 - Pierre Edelbruck

  18. Architecture shopping list • Angular resolution as a function of  and  • Counting rate as a function of  and  • Resolution for Time of flight (100 ps ?) • Modularity • Do all telescopes look the same ? (shape & size) • Do we want to remove / replace a section ? • Energy range and resolution • Do we have (or can we be) ancillaries ? • Do we want transparency ? • If yes, what is transparency ? WG3 - Pierre Edelbruck

  19. Trigger • First Reflections (MF Rivet) • Trigger must be hardwired • Asynchronous mode: local trigger + global validation • Path should be fast in both directions (dead time reduction) • Organization • Multiplicity based on telescopes (not just single detectors) • Three detectors in the telescope managed by the same unit • All three sets of parameters always recorded • Coincidence window ~300-400 ns • Validation time < 1-1.5 µs, Star distribution • Clever telescope grouping in order to balance counting rates WG3 - Pierre Edelbruck

  20. Trigger • Miscellaneous • More elaborated information may be useful (additional threshold) • Need for a slow trigger to accommodate ancillary detectors or elaborated software trigger • Nature of the trigger information packet to be defined • Trigger system must be fast with dedicated lines • Pulser • Avoid firing all telescopes at the same time ! • Other lines also required • Clock • RF • … WG3 - Pierre Edelbruck

  21. Trigger • Giacomo’s note • 1 Local Trigger - Global Validation scheme • Only those detectors who have fired transmit data • Fine timing (100 ps) performed offline • 2 Local trigger to be fast and low threshold • Use digital filtering to lower threshold • Walk should be kept low (CDF ?) • 3 Multiplicity is not enough • A rough estimate of the energy would help • Position information is also important, also how many stages in the telescope have fired • Necessity of a programmable “trigger box” • Program based on the nature of the experiment WG3 - Pierre Edelbruck

  22. Trigger • 5 Refinement • An intermediate energy shaping could be performed, leading to a lower threshold, information available after local trigger but before validation. • 6 How do we physically organize the up and downstream communication path ? • 7 What hardware ? Why not an optical fiber. • 8 Dead time and event recognition • Event-counter and/or time stamp required ? WG3 - Pierre Edelbruck

  23. Trigger • Comments on Giacomo’s notes (Pierre) • System is fully digital • Past information fully available for several µs • Front End never stops working • No dead time (with the exception of the MAR chip) • Latency exists but should not hurt • Dead-time, Latency, Walk and Spread are four different things • Walk may reduce coincidence quality  digital DFC to be designed. Spread is more complicated • No strong real time requirement if events clearly dated • Time stamping with 10 ns resolution to be implemented • Required unique clock source for the whole system WG3 - Pierre Edelbruck

  24. Trigger A meeting in Florence WG3 - Pierre Edelbruck

More Related