Development and application of digital control technology of resonant excitation for quadrupole ion trap

The technology of control of resonant excitation is a key to improve the sensitivity and resolution and realize the multiple-stage mass spectrometry for quadrupole ion trap. Considering miniaturization is an important trend in mass spectrometer development, a method of amplitude modulation of direct digital synthesizer (DDS) realized by filed-programmable array (FPGA) software was proposed, and the digital control technology of resonant excitation and a new system whose hardware was simpler had been developed. In the electrospray ionization-rectilinear ion trap mass spectrometer which requires higher performance on resonant excitation control system than many of others, using the system, many functions had been realized including isolation of an ion, three-stage mass spectrometry, full scan in the range of m/z 600-2000 Thomson. The testing showed that the power consumption of the developed control unit was 10% of that using hardware to modulate amplitude, and the performance of the system met the requirement of quadrupole ion trap too.