The PDPC Technology Evaluation Kitmuon.npl.washington.edu/exp/NewG2/private/CaloDesign... · 2011. 11. 18. · PDPC Cruise Dinner June, 10th 2011 - Philips Digital Photon Counting

Ralf Schulze <[email protected]> Philips Digital Photon Counting

The PDPC Technology Evaluation KitYour Entry to Digital Photon Counting

mailto:[email protected]

PDPC Cruise Dinner June, 10th 2011 - Philips Digital Photon Counting

The PDPC Technology Evaluation Kit

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Overview

• Technology overview– Photon detection with SiPMs– Digital vs. analog

• The Philips Digital Photon Counting (PDPC) sensor• The PDPC Technology Evaluation Kit (PDPC-TEK)

– Components – Features

• Sample applications


Principle of Silicon Photomultipliers

● Operating diodes in reverse bias in Geiger-mode (above breakdown voltage)

● Single photon triggers breakdown of diode

● Diode breakdown can be detected and indicates photon hit

↪ Single photon detection

Voltage

Current

Time

VBD

Meta-stable

Breakdown

Quenching

VBiasV


SiPM Acquisition: The Analog Way

www.hamamatsu.com

● Photon detection current gives analog signal ● Number of detection photons determined by

peak-shape analysis

↪ Pulse shape analysis difficult, influenced by external parameters (magnetic field,

noise, temperature, etc.)


dSiPM Acquisition: The Digital Way

● Photon detection signal is digital by nature (photon or no photon)● Keep further processing fully digital by counting number of cells that broke

down with on-chip digital electronics (Adder circuitry, TDC, etc.) ● Chip output is digital number of photons with timestamp

↪ Fully digital processing chain ensures minimal impact of external parameter changes and greater flexibility


PDPC Sensor Structure

● Configurable event validation (on sub-pixel and pixel level)

● Integrated TDCs on die● Integrated event adding

↪ Timestamp and number of detected photons per pixel


PDPC Sensor Array

● 8x8 pixels per array● Readout and control electronics● Temperature sensor● Data correction and calibration

data stored on array● Time sorted events● Upgradeable firmware

↪ Smart tile

PDPC Cruise Dinner June, 10th 2011 - Philips Digital Photon Counting 9

PDPC TEK Components

Up to 4 smart tiles Base unit for sensor control• USB 2.0 connection

• Supports up to 4 smart tiles

Preinstalled Linux laptop

• Control software

• Calibration tools

Power supplies for base unit


The PDPC Technology Evaluation Kit(PDPC-TEK)


Linux Based Control Software

• Command line interface

• Scriptable for automated measurements

• Source code included for own modifications or integration in own acquisition infrastructure


Software: Testing Capabilities


Software: Sensor Status (Power, Temperature, ...)


Further Software Functionality

• Adjustment of acquisition parameters

– Event validation (thresholds, photon triggers, ...)

– Acquisition settings (integration interval, cell recharge timings, ...)

• Data acquisition

• Calibration for photon saturation, TDC linearity, …

• Temperature monitoring

• Bias voltage adjustments

• Dark count rate measurements

• ...


Performance Enhancement by Saturation Correction

p=−N⋅ln(1−k N )N: active cellsk: triggered cellsp: # of photons

Digital acquisition allows correction of saturation effect

● Saturation curve upload to smart sensor array

● Automated, on-array correction before readout


dSiPM: Dark Count Rate Mapping

● Dark count rate specific to cell● Influenced by production process, radiation damages, ...● Few cells with very high rates

↪ Disabling a small percentage of cells can improve performance significantly


Comparison of High Dark Count Diodes Influence

Analog SiPM

High dark count cells influence pulse shape

↪ One single cell may render analog SiPM useless

Digital SiPM

High dark count cells can be selectively

disabled

↪ Digital SiPM still functional


Disabling High Dark Count Cells

● Scanning sensor with single cells in pixel enabled (software based)● Measurement of dark counts allows detection of high count rate cells● Upload inhibit memory map to sensor for cell deactivation

↪ Dark count conditions already improved without chip cooling

Pixel 1 Pixel 4 Pixel 1 Pixel 4

Dark count map Inhibit memory map


Application: Slow Scan Imaging

● Measurement with single cells enabled● Scan over full sensor area● High resolution imaging, although slow (~15 min acquisition)


Coincidence Measurements


Timing Performance (Demonstrator Chip)

Preliminary


Your Application Here

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The PDPC-TEK: What You Get

● Hardware:● Smart tiles (1-4)● base unit for tile control and

readout● laptop (preinstalled)● power supplies● cabling

● Software for configuration, measurement, testing (source code included).

● Firmware for sensor array and base unit

● Setup, testing and training on site

● 3 years of support


http://www.philips.com/digitalphotoncounting


The PDPC dSiPM Sensor

● 4 pixels per sensor● 6396 cells per

pixel● On-chip

● validation,● timing, and ● control logic.

Documents

The PDPC Technology Evaluation Kitmuon.npl.washington.edu/exp/NewG2/private/CaloDesign... · 2011. 11. 18. · PDPC Cruise Dinner June, 10th 2011 - Philips Digital Photon Counting