Development of Dose Readout Electronics for Proton Therapy Ionization Chamber

A set of nozzle equipment for proton therapy is now being developed in China Institute of Atomic Energy. To measure the transferred dose, a set of dose readout electronics was developed, which can be used to read and test the signal generated by the ionization chamber. The integral and amplification of input charge are realized by the precision low noise integrator IVC102. DSP56F82 is the main controller which controls the ADC to realize data acquisition and processing. Modbus communication protocol is used to establish the communication between the device and the host computer. Also, a charge generator to generate a fixed amount of charge was designed. The test results show that the relative error of the electronics, under the test charge from 20 pC to 2 μC, is less than 0 62%, which meets the design requirements.