设计为单端输入,选择64增益,参考电压4.86,AINP与AINN之间20mv时,读取adc值都只有0x2e7c(11900),远小于文档中的满量程2^17。
目前改变输入电压,得到的adc值是线性的。但是远小于量程设定的值,感觉增益不是64或者128,而是1.7或者3.4。通过示波器抓过数据脚DOUT了,确认高位确实都是0。
This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
共模输入范围是(AINP+AINN)/2 的值需要在[AGND+1.5V, AVDD-1.5]范围内;
电路图您可以参考ADS1230REF User's Guide,在这个应用指南最后面提供了原理图:
https://www.ti.com.cn/cn/lit/ug/sbau125a/sbau125a.pdf