Adding despiking capacitors

You can add these capacitors in the schematic like you would add any other part and connect them to the chip the way you would connect any other parts.  On the schematic, it doesn't matter where you place the capacitors physically, but they should be connected directly to the chip electrically.  When you make your board, then you can place the parts very close together.

The INVOKE command is used for the chips themselves and allows you to place part of the chip on your schematic.  For example, if you have a quad op amp, you can invoke any of the four op amp circuits.  If you don't use one or more of the op amps, you don't have to invoke them and they won't show on the schematic.

Dear Don Hersey,  mcb1 + Doug Wellington,

Wow!!!! Very fast and awesome response!! Thank you so much gentlemen. Yes, very correct, one just has to place them in the schematic and then later move them closer to the chips. I am now after I read the insight on, "over use" of these caps........thinking of.......instead of one cap per chip, perhaps will use......one cap per two chips. It is very easy to overdo this decoupling/despiking thing. The currents will start to breath instead of flow on the tracks.

I am designing my power tracks 3 times ticker then my signal tracks also, much better for the overall impedance.

Thx again gentlemen!

Cheers,

peter

Yes it is possible to "over decouple" your supply by having too many large capacitors  however it's generally better to have many small (say0.1uf) capacitors by every chip than having a larger one every so often. Each small capacitor supplies decoupling to each chip in turn which is what you are after!

And that was with no redundant cooling system.

Once we went to transistorized equipment, the rodent problem in winter seemed to also drop.

Mark

An interesting read:  http://en.wikipedia.org/wiki/Compactron

I remember back in '68 or so Popular Electronics had an article on a guy

with some sort of surplus computer he purchased. All tubes.  Took up his

whole shop and required something like a 20 ton air conditioner to keep it

cool.

mikey

--

Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

remember the old "compactrons"

No sorry don't recall those, but I do recall the introduction of 'thick film technology'

An engineer came and spoke to us and told us they were far too complicated for us to understand.

(he was lucky the high voltage was away that day)

We used the valve transmitter for the taxi channel as a 'pie warmer' (before microwaves) at a station ... very handy.

Mark

remember the old "compactrons"

No sorry don't recall those, but I do recall the introduction of 'thick film technology'

An engineer came and spoke to us and told us they were far too complicated for us to understand.

(he was lucky the high voltage was away that day)

We used the valve transmitter for the taxi channel as a 'pie warmer' (before microwaves) at a station ... very handy.

Mark

And that was with no redundant cooling system.

Once we went to transistorized equipment, the rodent problem in winter seemed to also drop.

Mark

An interesting read:  http://en.wikipedia.org/wiki/Compactron

I remember back in '68 or so Popular Electronics had an article on a guy

with some sort of surplus computer he purchased. All tubes.  Took up his

whole shop and required something like a 20 ton air conditioner to keep it

cool.

mikey

--

Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.