Quote Originally Posted by The Master View Post
Hi, The regulators are the correct way. I did make that mistake in the original design but luckily realised before i etched the PCB and plugged the servos in. They are running from a 12V supply so they probs wouldnt last long if the regulators were wrong.
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(12v - 5v) * ~350 mA ( servo w/ small load ) = 2W per regulator

is it enough to show ???

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The power supply is a desktop PSU (similar to a laptop PSU) and it is capable of outputting 7A. As far as i understand the voltage is correct so 7A shouldnt cause a problem but im not overloading them am i?

Ive opened the skull (yes, skull!) and turned the servos on. It seems that at least 3 of them are constantly twitching but its not noticable just by looking at them. I know that will cause a huge power drain through the regulators but i wouldnt have thought the servos would mind as they are designed to constantly correct their positions.

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your servos should have no load other than moving parts of your skull ... especially no STATIC load ... ( like compressing a spring coil )
so, all moving parts have to be balanced to create a minimum load on the servo @ " neutral position " or steady positions ...

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I think the slight twitching could be caused by my code but it is written in assembly and goes into a tight loop before the timer overflows so it should be accurate to 400ns.
I do not think it's a real problem ... theres a " deadband " around the steady position : about 2µs to 10µs ( from best to worse servos )

Now ... some servos draw not negligible current to hold position with very light loads ... some need quite a load to begin to draw current ...
This belongs to servo caracteristics ...

Say ... the smaller the servo, the Higher the current draw @ 1kg*cm torque i.e.

from 250 mA to 750 mA ... depending on the servo size and ... brand.

Alain