Speaker
Description
To address the beam diagnostics requirements of multiple cyclotrons at China Institute of Atomic Energy (CIAE), a multi-channel digital beam diagnostics electronics system based on current-to-voltage (IV) conversion was developed. The IV conversion circuit integrates high-precision operational amplifiers with ultra-low bias current and low-temperature-drift resistors. The system implements a hybrid filtering architecture: analog filters and digital filters. The analog filters include the first-order RC filter and the second-order MFB low-pass filter, and the digital filters include the FIR filter, median filter, and MAF filter. Xilinx Artix-7 series FPGA(XC7A100T-2FGG484I) is used as the main controller and an 8-channel 18-bit resolution ADC(AD7606C-18) is used to realize analog-to-digital conversion. UDP protocol is selected as the communication protocol between the electronic system and the host PC or PLCs. Test results show that the max 0.5% relative error can be reached when the beam current ranges from 100 pA to 20 mA, with linearity R² > 0.999999 for all channels. The system has been validated through long-term operation on CIAE’s high-current accelerators (e.g., BNCT and neutron imaging accelerators, with the 16-channel electronics) and low-current accelerators (e.g., 16 MeV and 9.5 MeV cyclotrons, with the 8-channel electronics).
