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ATLAS PCB Tester
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Project Overview
Through the Electronic Design Facility (EDF) at Boston University I designed a testing interface for detection circuits used in a physics experiment. More specifically, I needed to replicate the pulse from a single electron passing through a tube. As a result the testing interface needed to be extremely high precision, in accordance with standards at CERN, and be capible of quickly testing Mezzanine cards bound for the ATLAS experiment.
My Role:
Electronics Lead
I worked on formulating the first revision of this tester and the electronic design & assembly of the pulse injector circuit emulating an electron.
PCB Design
A big challenge was keeping very small negative voltages above the noise floor, and passing those signals reliably to the Mezzanine cards being tested. Differential pairing and short traces were used to combat these issues.
Schematic
This circuit generates very small negative voltages upon input from an FPGA. I implemented an AND gate system to send out pulses, which prevents false signals from being sent by chance.
Teamwork
I worked constantly with Eric the EDF director on the design, as well as with other undergraduates in the EDF developing the mechanical structure to hold our board. There are multiple other pieces of the testing interface which we had to interface with. As a result of meeting constantly we had no major hiccups in our compatibility or performance.
What is ATLAS?
ATLAS is one of two general-purpose detectors at the Large Hadron Collider (LHC) in CERN. The specific experiment I assisted with involves the decay of a muon particle, which must produce an electron as a result. By capturing the path of the electron as it exits the LHC garners insights into how the muon decays and what other particles the muon decayed into.
Requirements
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Send very small negative voltage pulses
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Extremelyhigh fidelity
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Compatible with several types of Mezz cards
Highlights
I frequently gave presentations to our team to inform them of my board's status, and we caught several large compatibility issues early in the development stages. This saved us time and resources to be put towards developing this interface further.