Re: ESD problem
>What do you mean by "my circuit go down" ?
I wanted to say: it stops to work.
It's strange because it seem that some voltage regulator (78XX type) of my circuit start to work badly, and the only remedy is switch off the power.
>If your signal from the sensor is not changing too quickly, you can isolate it with a >voltage to frequency converter -> opto isolator-> frequency to voltage converter.
>You would also need an isolated DC/DC converter for the 5V supply and of >course spike protection, such as a transzorb. Perhaps you can just use spike >protection only.
The frequency conversion it's a good idea , but in my case it's not possibile put an IC near the sensor.