Preferred power supply connections?

dingebre wrote on Wed, 24 February 2010 21:57

The schematic I am "capturing" are based on public domain circuits for

audio processing modules in a modular analog synthesizer. There are some

standard power connection schemes which I intend to follow consisting of

+/- 15 Vdc and ground. Typically, the +/- supplies go through a ferrite

bead and a couple of filtering capacitors before hitting the PCB's power

nets.

 

What is the best way to make a power net for the PCB components bcause

it is separated from the power input jack by the ferrite bead? If I

connect the connector pins to the supply +15 and -15 nets, I can't use

them on the PCB. So, what is the best net to use to PCB components to the

other side of the ferrite beads? Should use one of the other available

supply nets or make a unique power net?

 

I have played with different ways to do it, and they seem to work, but

as I'm new at this capture stuff, I'd like to know if there are standard

or preferred ways to accomplish this.

 

This image kind of shows what I mean.

Hi David,

There are a few ways to do it.  First, every signal name in EAGLE is

global.  So if you simply name a net to a signal name it will be connected

to any other net with the same name whether it looks like it or not.  So

watch yourself there.

So you have a pin connected to a ferrite that goes to a plane then you can

do a few things:

1)  name (and label) the net between the pin and the ferrite.  That can be

helpful.

2)  create a custom supply symbol that indicates  it's function.  This can

work too and can help with readability if that net goes somewhere else

(like a raw power bus).

My rule is that I should be able to tell 100% what is happening in the

schematic when I print it out.  If you have to use EAGLE itself (by using

the info command for instance) to figure out what is going on then the

schematic is incomplete.

I also have a preference for labels over spaghetti nets that are hard to

follow when printed out.  Hope that helps.

Cheers,

James.

--

James Morrison  ~~~  Stratford Digital

email:  james@eaglecentral.ca

web: http://www.eaglecentral.ca

Specializing in CadSoft EAGLE

• Online Sales to North America

• Electronic Design Services

• EAGLE Enterprise Toolkit

--

Browser access to CadSoft Support Forums at http://www.eaglecentral.ca

dingebre wrote on Wed, 24 February 2010 21:57

The schematic I am "capturing" are based on public domain circuits for

audio processing modules in a modular analog synthesizer. There are some

standard power connection schemes which I intend to follow consisting of

+/- 15 Vdc and ground. Typically, the +/- supplies go through a ferrite

bead and a couple of filtering capacitors before hitting the PCB's power

nets.

 

What is the best way to make a power net for the PCB components bcause

it is separated from the power input jack by the ferrite bead? If I

connect the connector pins to the supply +15 and -15 nets, I can't use

them on the PCB. So, what is the best net to use to PCB components to the

other side of the ferrite beads? Should use one of the other available

supply nets or make a unique power net?

 

I have played with different ways to do it, and they seem to work, but

as I'm new at this capture stuff, I'd like to know if there are standard

or preferred ways to accomplish this.

 

This image kind of shows what I mean.

Hi David,

There are a few ways to do it.  First, every signal name in EAGLE is

global.  So if you simply name a net to a signal name it will be connected

to any other net with the same name whether it looks like it or not.  So

watch yourself there.

So you have a pin connected to a ferrite that goes to a plane then you can

do a few things:

1)  name (and label) the net between the pin and the ferrite.  That can be

helpful.

2)  create a custom supply symbol that indicates  it's function.  This can

work too and can help with readability if that net goes somewhere else

(like a raw power bus).

My rule is that I should be able to tell 100% what is happening in the

schematic when I print it out.  If you have to use EAGLE itself (by using

the info command for instance) to figure out what is going on then the

schematic is incomplete.

I also have a preference for labels over spaghetti nets that are hard to

follow when printed out.  Hope that helps.

Cheers,

James.

--

James Morrison  ~~~  Stratford Digital

email:  james@eaglecentral.ca

web: http://www.eaglecentral.ca

Specializing in CadSoft EAGLE

• Online Sales to North America

• Electronic Design Services

• EAGLE Enterprise Toolkit

--

Browser access to CadSoft Support Forums at http://www.eaglecentral.ca

James Morrison wrote on Thu, 25 February 2010 09:52

dingebre wrote on Wed, 24 February 2010 21:57

The schematic I am "capturing" are based on public domain circuits

for audio processing modules in a modular analog synthesizer. There are

some standard power connection schemes which I intend to follow

consisting of +/- 15 Vdc and ground. Typically, the +/- supplies go

through a ferrite bead and a couple of filtering capacitors before

hitting the PCB's power nets.

 

What is the best way to make a power net for the PCB components

bcause it is separated from the power input jack by the ferrite bead?

If I connect the connector pins to the supply +15 and -15 nets, I can't

use them on the PCB. So, what is the best net to use to PCB components

to the other side of the ferrite beads? Should use one of the other

available supply nets or make a unique power net?

 

I have played with different ways to do it, and they seem to work,

but as I'm new at this capture stuff, I'd like to know if there are

standard or preferred ways to accomplish this.

 

This image kind of shows what I mean.

 

Hi David,

 

There are a few ways to do it.  First, every signal name in EAGLE is

global.  So if you simply name a net to a signal name it will be

connected to any other net with the same name whether it looks like it or

not.  So watch yourself there.

 

So you have a pin connected to a ferrite that goes to a plane then you

can do a few things:

 

1)  name (and label) the net between the pin and the ferrite.  That can

be helpful.

 

2)  create a custom supply symbol that indicates  it's function.  This

can work too and can help with readability if that net goes somewhere

else (like a raw power bus).

 

My rule is that I should be able to tell 100% what is happening in the

schematic when I print it out.  If you have to use EAGLE itself (by using

the info command for instance) to figure out what is going on then the

schematic is incomplete.

 

I also have a preference for labels over spaghetti nets that are hard

to follow when printed out.  Hope that helps.

 

Cheers,

 

James.

Yes, it helps a lot. Thanks James. In the software I have been using

(competing commercial application), it was a real chore to do this kind of

connection and I was a litte nervous as it seems so easy to do in Eagle

I wanted to make sure I wasn't missing something.

David

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