# Design and Development of SyMPET: System on chip Modular readout for high-resolution TOF-PET

> **NIH NIH R44** · NALU SCIENTIFIC, LLC · 2024 · $1,022,870

## Abstract

PROJECT SUMMARY
Nalu Scientific LLC (NSL) proposes to develop and optimize the design of a silicon photomultiplier (SiPM)
based, low-power, high channel density, waveform-digitizing readout microchip for TOF-PET that will increase
image quality and provide more accurate and precise quantization, with the potential to significantly improve
early diagnosis or lower exposure while also allowing greater flexibility in the development of personalized
patient imaging strategies. The key idea behind the project is that of using the information of the full waveform
acquired from the sensors that can provide information to overcome the limitations of traditional approaches,
like the very fine accuracy in the threshold definition, dependence on low and high frequency noise, necessity
of ad-hoc corrections for waveform amplitude (“time-walk”) and shape variation, and imprecise energy
information, as well as no information about depth of interaction.
NSL’s patented waveform-digitizing “System on Chip” readout ASIC technology has the potential to
substantially improve TOF-PET imaging from its current state. During Phase I, we developed analytic modeling
of light production and transport in scintillating crystals, along with realistic simulations of sensor and readout
electronics in order to derive baseline technical specifications for a WFD readout chip. We then implemented a
machine learning model to harvest and demonstrate the benefits of WFD. In phase II, we will complete the
design, fabricate and test a SiPM-based, low-power, high channel density, waveform-digitizing readout
microchip for TOF-PET, and validate the concept by developing and testing a PET subsystem as a
demonstrator. We will collaborate with Dr. Hamid Sabet (Harvard) in improving the modeling of phase I,
defining the advantages and limitations of the use of waveform information in a full PET system setting, and
implementing a flat-panel PET detector demonstrator. The project specific aims are 1: Design and Fabricate
Waveform digitizer chip for PET applications. 2: Design and Fabricate a DAQ system for PET incorporating the
WFD readout chip. 3: WFD-based Detector Assembly Integration and characterization.
In Phase II, in order to reach the specific aims, we will complete the design of the prototype chip following the
specifications derived in phase I, using state of the art tools to confirm the functionality and performance of the
chip before fabrication and verifying it with thorough testing. We then will fabricate a DAQ system capable of
synchronizing multiple copies of the readout chip and handling expected data rates from realistic TOF-PET
detector environments, and finally evaluate them in a realistic condition using phantom testing.
The successful completion of the work is expected to result in the definition of a novel readout device and
system that could prove transformative for the field of next generation PET scanners.

## Key facts

- **NIH application ID:** 11008896
- **Project number:** 9R44MH140338-02A1
- **Recipient organization:** NALU SCIENTIFIC, LLC
- **Principal Investigator:** Luca Macchiarulo
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $1,022,870
- **Award type:** 9
- **Project period:** 2021-09-30 → 2026-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/11008896

## Citation

> US National Institutes of Health, RePORTER application 11008896, Design and Development of SyMPET: System on chip Modular readout for high-resolution TOF-PET (9R44MH140338-02A1). Retrieved via AI Analytics 2026-05-28 from https://api.ai-analytics.org/grant/nih/11008896. Licensed CC0.

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