Strong Bulk Bias Why ?

[gafsos]

Hello,

What are the effects if we design a poor Bulk Bias ??

Thanks

 

[leo_o2]

It might have latch-up problem or current leakage.

 

[jeevan.life]

It might have latch-up problem or current leakage.

Exactly....The device must be tied to bulk strongly...The main reason is latch up..other thing is that is not provided with sufficient connections the n well or the base layers will have to do the job of conduction...Due to their high resistance it is not usually preferred.

 

[dgnani]

Hello,

What are the effects if we design a poor Bulk Bias ??

Thanks

Even if you use enough bulk contacts to avoid latchup, you can still have problem with excessive resistance (some designs can be sensitive to large bulk resistance) and larger substrate noise, which can cause crosstalk and is very hard to simulate

 

[dick_freebird]

A weak body tie lets the body move with the gate, a
"dynamic threshold" on transient edges. It may help you
for digital flat-out speed but also can add a history effect
which gives you timing variation, offset variation in analog
exposed to variable switching activity, etc.