Part Number: ADS1118
Other Parts Discussed in Thread: ADS1115
The ADS1118 datasheet states that the data-rate can vary +/-10% from the programmed value. Can you comment if this is simply part-to-part variation or if the data-rate also have VT dependence.
Our application requires knowing the data-rate ahead of time, which we can measure at startup. But we need to know if the data-rate value measured at startup would drift across time and if so, how much is the drift?
Renaldi,
The internal oscillator of the ADS1118 is the same as the one in the ADS1115 and should the same basic performance. I'm not sure why the plot showing basic oscillator variation was removed in the ADS1118, but looking at the plot from the ADS1115, you can see that there is some variation of the oscillator frequency based on the temperature and the power supply voltage. Below is the plot taken from the ADS1115:
As listed in the datasheet, we don't give a min, max, or typical specification for oscillator frequency drift. We only use an absolute minimum and maximum of ±10% for the data rate. However, the the typical characteristics curve should show how much drift and variation you might see in a typical unit.
Joseph Wu
