How powering PIC in auto ?

[fratello]

If 5V6 it's not so good, what value do You suggest ?

[Gusse]

Working voltage of TVS (or any protection comp) must be a little over max DC voltage to avoid current leakage thru protection comp.

For de-rating you should use + 10-20%. This means that Vbr (breakdown voltage) value is important, it should be so much above normal DC voltage that you will never reach that in normal conditions.

5.6Vdc is usable (Vbr for that is ~6.5V or bit higher). With higher Vdc components (e.g. 7-10V) you will have less leakage.

BR,
-Gusse-

[fratello]

OK ! Thank you both verry much !

[amgen]

looks like the main reason for PIC is to check current to disconnect relay when window is all up or down ??
don
amgen

[fratello]

The reasons for using PIC :
-small circuit
-two different function (up and down) with two possibilities (long/short press)
-detecting over-current
-huge support from this forum (thanks again !)
-personal ambition !

[amgen]

you may want to add free wheeling diode across each relay coil, common practice because of the voltage spike generated by relay coil when released (switched off)

don
amgen

[fratello]

Please read post #4.