I'm currently using the fixed versions, both 3.3V and 5V of the LM2576 in our design. When the PCB is powered up, we are seeing up to -2V on both the 3.3V rail and 5V rail. See scope capture below:
Here is a view of our schematic:
DC input is 24V. We see the spike regardless of load applied or no load applied. This negative spike is possibly getting into a DAC chip through the 3.3V rail downstream and destroying it.
Any ideas on how we can remove this negative 2V spike?
Regards
Terry
