when I set the conf register to 0xd5, the ch1 register to 0x05, using internal reference. The signal's amplitude is around 7.5 mV, which is not the same as 2x-(Vrefp-VrefN)/2400 in the datasheet.
I have read this link [常见问题]关于TI ADS129x系列生物势ADC的常见问题 - 数据转换器论坛 - 数据转换器 - TI 端对端支持论坛. However, I did not find the solution. If convenient ,could you offer me a link, thanks!