Patent attributes
The present invention relates to a data processing device for mass spectrometry, in which measurements are performed in a high dynamic range without causing an overrange in an A/D converter in any TOF scan. A data acquisition circuit of a mass spectrometer includes an amplitude value computing circuit which measures and stores a maximum amplitude value of an ion detection signal, a gain control circuit for determining and setting a gain amount for the next measurement, and others. From the immediately preceding TOF scan data or TOF scan data plural times before, the maximum amplitude value of the ion detection signal is extracted. Then, before the next TOF scan, an optimum gain amount is determined based on the extracted maximum amplitude value to adjust the gain of the input signal, and the ion signal is sampled in the A/D converter.