zener tolerance effect..

:roll:
hi,

i'm having an electronic module that consists of zener diode (30v,2%BZV55B30V MINIMUM).
Ii i replace this diode with same spec but 5%,then what will happen?
both are working fine but in which condition it will give problem if i put 5% instead of 2%?

thanks.............

jaikanth said:

:roll:
hi,

i'm having an electronic module that consists of zener diode (30v,2%BZV55B30V MINIMUM).
Ii i replace this diode with same spec but 5%,then what will happen?
both are working fine but in which condition it will give problem if i put 5% instead of 2%?

thanks.............

Click to expand...

It depends entirely on the application, there might not be any reason for a 2% zener being specified anyway, and the zener you fitted may well be within the 2%!.

If it bothers you, measure the voltage across it, and see if it's within 2% of 30V.

A 2% Zener isn't the most common type, so just off the top of my head I suspect they went out of the way to select that one because the circuit does require a tighter tolerance.

That tolerance applies to the intitial "guaranteed" zener voltage at a specified current. In all likelihood, both the 5% and the 2% parts will "hold" their voltage equally as well with regard to again. As mentioned, if the voltage measures within the 2% margin, I'd go ahead and use the 5% part.

It might be that the 2% part is also temperature-compensated by placing another diode internally in series. These types of zeners don't have a "forward" conducting curve but appear as open.

Dean