DPA424PN Problem

Posted by: daniel_alemoraes on 03/20/2014

Hi,

I would like to some help to solve the problem of figure DPA424PN. The sign in blue is the source output 3.3V and yellow signal is the voltage Vds of DPA424P. What could be done to reduce this problem of noise at the output of the source?

Thank you in advance,

Daniel Mores

Files

24VDC_FINAL.uds (288.5 KB)

DPA424PN.jpg (37.5 KB)

Comments

Hi,

When you make this measurement, make sure use a voltage probe with very short loop between the probe and the ground lead. This noise may be caught by the probe itself, which is not real.

If you want to reduce this noise level,you could add filter capacitor or post filer (inductor+capacitor) on the output.

Hi Terry, Really with the probe voltage with lower ground loop eased the problem, but even with the post filter persists the noise at the output, which prevents even perform microcontroller´s recording of my application .
Attached the mounting generated by PI Expert software. Would you have any other suggestions?

So the 3.3V output is provide the supply for the micro-controller, a 1uF + 4.7nF capacitor can be put very close to the micro-controller to filter this noise.

Did you have any issue of the micro-controller with current supply? Would you please let me know what is the issue?