Hi team,
My customer has a project of pressure transmitter. They found the output codes have lower than 100bit jitter with 40Hz sps, and the output codes have more than 1000bit jitter with 1.2k sps.
In addition, they use one SPI from MCU to connect 4 ADS1262.
Below is the schematic:
Is there any way to decrease the output jitter?
BR,
Moon
Hi Moon,
The higher data rate, the higher noise, this is true on all precision ADCs. You can see the following noise table from ADS1262 datasheet, the noise at 1.2ksps data rate is much higher than the noise at 50sps data rate and the same Gain setting. 0.358uVrms(2.319uVpp) at 50sps vs. 1.743uVrms(13.428uVpp) at 1.2ksps at Gain=1. The customer can check whether the noise on their circuit board is similar as the noise shown in the following table or much higher than the noise in the table. If the noise is much higher, it could be caused by other reasons, for example, PCB layout and ground design, I have seen several different ground connections in the schematic.
BR,
Dale
