In order to improve the reliability and accuracy of synthetic test

a digitized synchronous control method is presented.The system

taking the single chip processor as its core

can calculate automatically the operation time of voltage source circuit and prolong arc circuit according to the testing parameter set by users

and adjust the injecting time through adjusting the output of D/A converter on line.The system has such functions as automatic zero adjustment and on line error modification to improve the control accuracy.The hardware circuit is designed and the corresponding program is coded and debugged.The experimental result indicates that the digitized synchronous control method is of better real time and high precision

which ensure the success rate of synthetic test.