Hello all,

I know in bipolar or Bicmos processes sometimes ESD protection structures are based on bipolar devices and their associated breakdowns. Primary breakdown is usually well defined in a process and also the associated resistance under such condition is well known. These two parameters are the main ones for defining which ESD level the protection will be capable of reaching.

Does anybody have any experience with protection structures also using secondary breakdowns of bipolar devices for providing further ESD protection (higher level)? If so could you please share the main limitations and advantages associated to it?

Many thanks in advance
Regards
Tosei