Tool/software:
Hello all,
I have a Bidirectional, Dual Active Bridge board that is based on the TIDA-010054. However, whenever a DC bus is applied (even as low as 50 VDC), the 3.3 V PWM signals at the power board exhibit strong ringing/glitches correlated with the switching edges (PWMs running at 100KHz).
Differential probe on power nodes (as shown in red in the above image); passive probe on logic lines. The scope and DC supply share the same AC outlet.
As shown below on the left, the PWM signal without putting my probe at the output. On the right, I am measuring the output of the inverter (in blue) using a differential probe (1:200).
The frequency of the ringing on the digital PWM is ~90MHz and for the output, it is about 30MHz. I am running the board at 200VDC.
What is causing this ringing/noise on my PWM signal despite the board having isolated gate drivers?
This image below is when I touch one of the output connectors with the probe or anything !? The ringing amplitude gets bigger !?
Thank you all,