Hi,
I have a system which use ADS1292R for ECG signal sampling. The ECG sampling channel is channel 2, and I use chanel 1 for monitoring the AVDD. I found a strange problem, when the lead connected to channel 2 is off , the AVDD calculated from channel 1 data is correct. However, when the Lead is attached to human skin or ECG simulator, the measurement of AVDD become unstable and incorrect. For example, the battery voltage is 2.7. At the lead off condition, the measured AVDD is around 2.7, but when the lead is connected to skin or simulator, the measured AVDD is sometimes as low as 0.3, sometimes as high as 3.1 .
I wonder is this the build-in behavior of the ADS1292, or may it related to the circuit design or register config?
The following is my register config:
const uint8_t ADS1x9xR_Default_Register_Settings[15] = {
//Device ID read Ony
0x00,
//CONFIG1
0x02, // 500sps
//CONFIG2
0xE0,
//LOFF
0xF0,
//CH1SET (PGA gain = 6)
0x13,
//CH2SET (PGA gain = 6)
0x00,
//RLD_SENS (default)
0x00,
//LOFF_SENS (default)
0x0c,
//LOFF_STAT
0x00,
//RESP1
0x02,
//RESP2
0x03,
//GPIO
0x0C
};
Thank you!
Jingsheng
