Esd

E

e44-72

Member

• May 15, 2012

• #1

Hello

I don't understand why if you touch a static sensistive chip such as cmos it damages it. Say I had a static charge of 50 volts, if I touch the chip it too would become the potiential of 50 volts, why would there be any current flow if the chip is no connected to ground.

Thank you for reading

 

WTP Pepper

Active Member

• May 15, 2012

• #2

The problem with ESD discharge is we maybe talking of 50,000+ volts and not 50. As you pick up an IC by the pins, there is most likely a potential difference momentarily and that's enough to puncture the several nanometer (uncited, but it's pretty thin) thick insulated (before you picked it up!!!) CMOS gate.

 

E

e44-72

Member

• May 15, 2012

• #3

Thank you for your reply, so say I pick the ic up by the body so its off a surface then put my hands of the pins, is there a discharge then or is their not and would that cause esd damage.

 

Last edited: May 15, 2012

WTP Pepper

Active Member

• May 15, 2012

• #4

Never touch the pins. Push into a piece of tin foil to equal all the pins or an anti-static bag where yes, all maybe at 50,000 volts but the potential diff will be close to zero.

 

E

e44-72

Member

• May 15, 2012

• #5

Ok, thanks for the reply wtp pepper.