TOF Mass Spectrometer Data Acquisition Merging Time-Intensity Pairs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Time of Flight mass spectrometers face limitations due to Time to Digital Converters (TDCs) causing dead-time after ion arrival events and inability to distinguish between single and multiple ion arrivals, and conventional histogramming algorithms in Analog to Digital Converter (ADC) systems that suffer from performance constraints with SDRAM access.
Innovation Solution
A data acquisition method for Time of Flight mass spectrometers involving a processing module generating streams of time and intensity pairs, merging data across multiple memory banks to create merged data sets, and outputting a compressed spectrum with improved dynamic range and accuracy, utilizing burst read/write performance and time-ordered input events to enhance data streaming efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If TDC is used to record ion arrival events, then ion arrival time can be recorded, but dead-time occurs after each ion arrival event during which no further events can be recorded
Solution Approach 1:
The patent segments the recording function into two distinct components: TDC for precise time measurement and ADC for continuous signal recording. This segmentation allows each component to operate independently without the dead-time limitation affecting the other, thereby maintaining high recording rates while preserving time measurement precision.
Solution Approach 2:
The patent introduces an intermediary processing stage that receives signals from both TDC and ADC, combines their data, and produces the final spectrum. This intermediary layer integrates the precise timing information from TDC with the continuous amplitude information from ADC, resolving the contradiction between measurement precision and productivity.
2Ease of operation
If TDC uses a fixed amplitude threshold to trigger recording, then simple detection is achieved, but inability to distinguish between single and multiple ion arrivals occurs
Solution Approach 1:
The patent merges the output of TDC (time information) and ADC (amplitude information) into a unified data structure. By combining these two data streams, the system simultaneously achieves simple threshold-based triggering from TDC and the ability to distinguish single from multiple ion arrivals using ADC amplitude data, resolving the contradiction between operational simplicity and measurement precision.
3Quantity of substance
If conventional histogramming algorithm is used with SDRAM, then data can be stored and processed, but performance is limited due to tens of clock cycles required for each access
Solution Approach 1:
The patent performs preliminary actions by pre-organizing data in a format that minimizes subsequent memory access requirements. The merged time-amplitude data structure is designed to reduce the frequency and complexity of SDRAM accesses, thereby improving processing speed while maintaining adequate data storage capacity.
Solution Approach 2:
The patent changes the data representation parameters from conventional histogram format to a merged time-amplitude format. This parameter change reduces the number of memory operations required per ion event, thereby improving processing throughput while maintaining the ability to store sufficient data for spectrum construction.
Data Source
AI summary
A data acquisition system for a TOF mass spectrometer comprises a processing module and a data collection module. The processing module generates a stream of data comprising, for each respective transient of a first scan, a set of time-intensity related parameter pairs. For each new set of data, the data collection module reads out a previous set of data from a previous memory bank, merges that previous set of data with the new set of data, and writes that latest merged set of data into a memory bank other than the previous memory bank. The data acquisition system provides a convenient way to merge sequential sets of time-intensity related parameter pairs for respective transients as a stream of data for a first scan is generated.