Electronics > Projects, Designs, and Technical Stuff
Really low value current sense resistor (50mV peak) will it have noise issues ?
Miyuki:
I have two phases
Blanking is supported
But datasheet is silent about noise transfered from CPU to comparators, or even detailed specs of comparators :-//
Layout can be tricky to avoid inductive coupled on sense line or ground issue as it will be single ended measure
fourtytwo42:
I use PIC's in similar situations but preceded the internal comparitor with an external differential op-amp r-r io kelvin connected directly across the sense resistor. Even so I use LEB as the noise in an hard switched SMPS of any power (mine are 1-3Kw) is substantial never mind how much care you take IMOP.
Miyuki:
I also considering use of high side sense like HV7802 it is reasonably cheap and can be placed before chokes to give much cleaner signal and have configurable gain
Miyuki:
I agree with amplifier right next to sense can voltage go much lower
Vovk_Z:
--- Quote from: Miyuki on May 04, 2020, 01:51:09 pm --- will noise just mess this low signal and Ill need to get some amplifier ?
--- End quote ---
The problem will be wires to that shunt (their lengths) but not the shunt DC resistance because they can be longer than the shunt itself.
Navigation
[0] Message Index
[*] Previous page
Go to full version