I am prototyping a device which will be able to measure ECG and two-electrode lead off. To do so I use the ADPD4101 but I am in trouble with your recommended configuration for ECG measurement with low DC offset. It concerns the INTEG_WIDTH_x, INTEG_OFFSET_x, MOD_WIDTH_x and MOD_OFFSET_x bits. Indeed, you give some relationship between those bits in Table 27, which are:
- MOD_WIDTH_x = 3 * RC
- INTEG_WIDTH_x = MOD_WIDTH_x + 1
- MOD_OFFSET_x = INTEG_WIDTH_x + 3
- INTEG_OFFSET_x = MOD_OFFSET_x −
INTEG_WIDTH_x – 250 ns
However, in your recommended configuration for ECG measurement with low DC offset (page 46), it seems that it does not respect the relationship between MOD_OFFSET_x and INTEG_WIDTH_x and the formula of INTEG_OFFSET_x. Indeed, with your recommanded configuration, I obtained (if I am not wrong):
- MOD_WIDTH_x = 2 µs
- INTEG_WIDTH_x = 3 µs
- MOD_OFFSET_x = 13 µs
- INTEG_OFFSET_x = 16 µs
Note that the same observation can be made with the two electrode lead off measurement configuration. So, what should I follow, the table 27 or the recommended configuration? I am a bit lost.
Thanks in advance.