高精度兩次采樣AD轉(zhuǎn)換

AD 轉(zhuǎn)換是測量中一個(gè)非常重要的部分，為了達(dá)到精度比較高的轉(zhuǎn)換效果，人們往往選擇位數(shù)較高的AD 轉(zhuǎn)換器，這樣容易造成電路的成本過高。本文就介紹一種如何利
用普通的AD 轉(zhuǎn)換器來實(shí)現(xiàn)高精度的AD 轉(zhuǎn)換，它利用兩次采樣的原理，通過一個(gè)模擬量進(jìn)行兩次轉(zhuǎn)換，從而實(shí)現(xiàn)高精度。此轉(zhuǎn)換器所需元件比較簡單，主要由一個(gè)凌陽SPCE061A單片機(jī)和一些普通的選通、運(yùn)放電路組成，文章從硬件電路的組成和軟件程序的編寫兩個(gè)方面來進(jìn)行說明，清晰的介紹了如何來實(shí)現(xiàn)高精度轉(zhuǎn)換的功能。
【關(guān)鍵詞】 AD 轉(zhuǎn)換，高精度，兩次采樣，原理
【ABSTRACT】In the scopes of measure, AD conversion is a very important part, the higher bit AD converter always is chosen in order to gain high precision, but it is very expensive for the circuit . With twice sampling theory, an analog voltage is converted twice to realize the high precision. The converter is composed of lingyang SPCE061A mcu, ordinary gates and amplifiers, it is simple. That how to realize the high precision conversion is showed clearly on hardware circuit and software programs in this article.
【KEYWORDS】 AD conversion, high precision, twice sample, elements