12 Servo's together does not seem to work, Power problem

[Bruce]

Any question about the concept?

What's the difference electrically?

[mister_e]

Well to me, if those connections are close, or simple header it doesn't make any difference as the PCB trace impedance will be pretty low. OK maybe a little more stress at the PCB trace source end but... Few mOHM @ few amp, don't make any difference to me. and we talk about few amps DC and/or low frequency stuff so...

If you had 1 single pair of cable from the PCB to multiple external servo, and each servo are hundred meters (or more) separated... maybe... but who wants to do it like this?

The theory is fair, but i don't believe it's as this critical here.

Sorry Sayzer

[sayzer]

I knew this was going to come out.
I was so lazy to draw all 12 servos. Here it is.

Now, it should make more sense.

In Figure3, S1 and S12 do not get the same voltage although they are parallel.
But in Figure4, all servos get equal voltage.


<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1260&d=1166037872" >





Edit: Schematic corrected upon Alain's warning.
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[Acetronics2]

I knew this was going to come out.
I was so lazy to draw all 12 servos. Here it is.

Now, it should make more sense.

In Figure3, S1 and S12 do not get the same voltage although they are parallel.
But in Figure4, all servos get equal voltage.


<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1259&d=1166036361 " >

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Hi,Sayzer

Sorry for the cold shower ...

But the signal pin is ALWAYS at pin 1 or 3 of the connector...

The two power lines are ALWAYS side by side !!!

Alain

[sayzer]

Thanks Alain.

I corrected the pins in post #10 and #13.

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