Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
The principles behind different ESD protection schemes must be fully understood as well as various ESD schemes that aim to create low impedance discharge paths to shunt ESD transients, clamp the pad voltages to sufficiently low levels and techniques that limit ESD currents from reaching the...
Re: Noise Isolation
The reason that some designers don't like separate bulk and source potentials is that is creates a body effect which can cause variations in the Vt. The body effect is created because you now have created a cap between the source and bulk.
REM: cap = two plates at...
Re: Noise Isolation
Number of substrate powers:
We only really need one quite substrate power IF and ONLY if we as layout engineers have ensured that we have done a good job in ensuring that the signal is quite all the way back to the pad.
The problem arises though that you may have done an...
Re: Noise Isolation
I completely agree Varma. The strategy HAS to be put into place at the very beginning, i.e. extra pins for the quite potentials etc..
The point is though that it is easy to change the noise strategy later on though if it's needed ( as some designers will argue the body...
Ok I've read through lots of posts regarding noise isolation and guard ring strategies and I like to add some import points:
Without doubt the one thing that layout people get wrong is guard rings. Very wrong in fact. Let's look at some examples:
1. What potential do I tie the inside of my...
Re: Substrate contact
You need to be very careful when placing substrate contacts down:
1. Filling empty space with PTAP reduces the effect you naturally get from field oxide, i.e. substrate isolation. If your substrate is noisy ( and it can be!), you have just brought all that noise up and...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
