LAUNCHXL-F28379D: TMS320F28379D ADC ePWM Spikes

Hello,

My experimental setup looks like this: I feed a DC signal to pin 30 of the Lauchxl-F28379D. This signal is sampled every 1.2us using ADC. The ADC is triggered using ePWM.
To check the ADC input, I measure directly at PIN 30 using an oscilloscope. It should be noted that a spike can be seen with each sample. But if I disconnect the connection to the board and only the pure DC signal messure, this spike is not to be seen. Where do these spikes come from?