The characteristics of vfc-type analog to digital converter ( atd ) and successive approximation analog to digital converter are analyzed . the paper disscuss the advantage of mcu integrated adc, select the data acquisition system of the design . 4 . this paper utilizes the monolithic silicon integrated circuit performs switch monitoring and switch operation 在開人、開出回路設(shè)計方面,分析了傳統(tǒng)開人、開出的不足之處,提出了對開人、開出回路進行改進的創(chuàng)新想法,設(shè)計了更為簡潔、可靠的開人、開出電路。