Is ERC checks are really dangerous..

Hi All,
I want to know , is the ERC checks are really dangerous that we need to take care or clear the erc errors. I have some ptransistors for which bulk connected to ground. I have lvs clean but not erc.
Giving error like..
"ntap connected to GROUND"

What to do?
what is erc(electrical rule check)?
Please give me some information about these topics.

Thanks in Advance.
bsrin

bsrin said:

I want to know, is the ERC checks are really dangerous that we need to take care or clear the erc errors.

Click to expand...

You're lucky to have run ERC!

bsrin said:

I have some ptransistors for which bulk connected to ground.
I have lvs clean but not erc. Giving error like.. "ntap connected to GROUND"

Click to expand...

This is a fatal error, if these ptransistors are used as transistors (and not as capacitors), because in this case their sources and drains would be short-circuited via forward-biased diodes to GND. This is a killing scenario!
The LVS can be clean, if the schematic contains the same fatal error.

bsrin said:

What to do?

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The bulk (ntap) of active ptransistors must have (at least) the highest potential of both their sources & drains, or VDD level, if possible.

bsrin said:

what is erc(electrical rule check)?

Click to expand...

Yes.

Hi erikl,
I have the pfet with gate , source, bulk connected to ground. So that , i am getting the erc error like " ntap connected to ground ". I asked the designer about these transistor and told that yes these pfet should have bulk connection to ground.
Can i ignore this erc error.....
what to do?

bsrin said:

Hi erikl,
I have the pfet with gate , source, bulk connected to ground. So that , i am getting the erc error like " ntap connected to ground ". I asked the designer about these transistor and told that yes these pfet should have bulk connection to ground.
Can i ignore this erc error.....

Click to expand...

Yes, in this case you can ignore it!

bsrin said:

what to do?

Click to expand...

Nothing, it's ok!

Many Thanks erikl........

bsrin said:

Many Thanks erikl........

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You are welcome!

bsrin said:

I have the pfet with gate , source, bulk connected to ground.

Click to expand...

And I hope, the drain also! Otherwise it will be short-circuited to GND, too! And also any other active device in the same nwell.