active short-circuit breaker for your amplifiers

[erhan739]

this circuit cuts in a short-circuit any time in a troubleshoot or a problem and protects your amp or your speakers

 

[metal]

Can you please explain how this circuit works to prevent short-circuit damage for the amplifier?

Thanks

 

[erhan739]

this circuit compares input and outputs. so quickly cuts outs and protects amplifiers not burns by short circuits

 

[DjLeco]

This is a DELAY turn on, just that.
To protect amp from schortcircuit, must sensed fragments of tensions from emmiter resistors, noy from inpout output!
Also protects speakers at DC out.

 

[Sierra]

This is a DELAY turn on, just that.
To protect amp from schortcircuit, must sensed fragments of tensions from emmiter resistors, noy from inpout output!
Also protects speakers at DC out.

First time I check this, I dont think it will protect from short circuit, since thats not an easy task

 

[Malmir]

An easy way to protect against short is to add a hall element in the power rails, load impedance lowers the currentflow raises, and thus the output from the hall. If You guess Your amp should stand a 2 Ohm load, then shut down at current flow "2 Ohm load" + a margin. Eg do it steped, as half the input if still wrong then control power supply to deliver half of voltage for output stage, and if still going wrong shut down the amp entirely.
The hall element is supplying a reference circuit to control some relays.

 

[CobraNet]

Hummmm

An easy way to protect against short is to add a hall element in the power rails, load impedance lowers the currentflow raises, and thus the output from the hall. If You guess Your amp should stand a 2 Ohm load, then shut down at current flow "2 Ohm load" + a margin. Eg do it steped, as half the input if still wrong then control power supply to deliver half of voltage for output stage, and if still going wrong shut down the amp entirely.
The hall element is supplying a reference circuit to control some relays.

.....

Can you show me a working design of this?

 

[Malmir]

Yes i should be able to, but i only have schematic tools at work, so i might take a little week or so to publish.

But short You need 2 hall elements for dualrail or for single power line supply. The one i have been using can carry about 120A (if i read datasheet correct) and outputs neer 1mv pr A going through. By meassuring this and compare with a "maximum", You could have a opamp to compare and then control the needed action.

Some one told me that MusicTronic also used hall elements but at output, but i do think it would be all to late to reakt on the output short current.

Just had an idea. If one makes a multi channel amp, then let the hall output to a multi channel adc and the to a microcontroller, by this You could meassure all amp modules but only needs to shut down the defected.

Ok i'll be back soon i hope .