In S32 Design Studio, we are using two methods for ADC peripheral configuration. The first method uses the BCTU trigger for current sensing, while the remaining channels, such as temperature and voltage sensing, are triggered using the normal ADC chain method.
When the CTU mode is configured as a trigger mode and only the three current-sensing channels are configured with the BCTU trigger, there is no noticeable current spike. However, when I include the remaining temperature and voltage channels using the normal chain method along with the current-sensing channels, the current-sensing values are affected by spikes.
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There is a timing difference between the two methods: the BCTU conversion is triggered through an interrupt, while the normal ADC chain is called from a 5 ms task.
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Could you please explain why this difference is causing the current-sensing spike and suggest how we can reduce or eliminate it?