Do you use a shielded cable? Unshielded cable will pick up noise.
Look for earth loops too, because it will pick up every radioation from the board or output coil. Connect common to safety earth pole on the AC plug.
Overload protection without shunt res.
Hi to all
One good engineer from my country was recommended to me cheap and very good solution for overload protection without SHUNT resistor. He used this schmatic many times (for 30 years) and this is good because can use with any amplifier including this.
Actually its electronic fuse, very fast and stable and good because it has trim pot for setting current when amplifier will shut down.
Look at the schematic and read the word document that I atached. I belive you can understand because I use google translate from serbian to english.
What are you think?
Regards
Hi to all
One good engineer from my country was recommended to me cheap and very good solution for overload protection without SHUNT resistor. He used this schmatic many times (for 30 years) and this is good because can use with any amplifier including this.
Actually its electronic fuse, very fast and stable and good because it has trim pot for setting current when amplifier will shut down.
Look at the schematic and read the word document that I atached. I belive you can understand because I use google translate from serbian to english.
What are you think?
Regards
Attachments
I short input to ground noise is less but still noticeable. And I use shielded input cable.So cable is not a problem.
"without shunt resistor" ???
There is a 0,3 Ohm + transistor shunt in your schematic.
It will dissipate more than a simple 0,033 Ohm shunt (for 20A current sense).
So this idea is idiotic. You can do better with only a shunt and 2 transistors per side.
An externally hosted image should be here but it was not working when we last tested it.
Here is my idea to decrease shunt dissipation. Current treshold can be set by the trimpot. By using a JFET the voltage need at shunt resistor is decreased (from 0,6-0,7V, to <0,2V), so as dissipation.
The 12V supply is all referenced to the auxiliary supply of the IR2110. So the ground in this schematic goes to negative supply, SD pin is the SD pin of IR2110.
I haven't tested this, I've only simulated it.
Why do you think everyone uses the same layout editor as you?
If you want help post things as, so we can help.
Please post pictures about your setup. (the module you built, with supplies... connected) I find my ask trivial, cause the problem is sure be there, then we can tell what.
This is my module. With +-42VDC .All on the heat sink is warm. Coil is cool.
