Hello folks, sorry for my bad english if I write something wrong please don't blame me.
So as you probably know there are many opamps without short circuit protection (many high current) so if I use it as a amplifier (for headphones etc.) and when I plug headphone jack there will be a short circuit and very big chance to damage opamp permamently.
Is there exist any schematic or IC that can I use to avoid opamp damage ? I don't want to make things worse in case of performance/sound quality.
Thank you hor helping me.
Regards.
So as you probably know there are many opamps without short circuit protection (many high current) so if I use it as a amplifier (for headphones etc.) and when I plug headphone jack there will be a short circuit and very big chance to damage opamp permamently.
Is there exist any schematic or IC that can I use to avoid opamp damage ? I don't want to make things worse in case of performance/sound quality.
Thank you hor helping me.
Regards.
That's quite a good question.
OK, here are my thoughts... firstly you have to be practical. Is the opamp you are looking at really going to self destruct the instant a short appears or is it more a case that its not protected long term against total abuse. For example there is a big difference running a device at its absolute max supply and temperature, driving it hard and then shorting it. If its protected then it will survive 24/7 under those conditions. The unprotected one may well survive several seconds or more in practice.
The only easy to add any kind of protection would probably be some foldback limiting of the supplies, arranged so that any current drawn over the maximum would limit automatically with the rail folding back to a lower level too.
I suspect that there probably isn't an issue for the type of use you have in mind.
OK, here are my thoughts... firstly you have to be practical. Is the opamp you are looking at really going to self destruct the instant a short appears or is it more a case that its not protected long term against total abuse. For example there is a big difference running a device at its absolute max supply and temperature, driving it hard and then shorting it. If its protected then it will survive 24/7 under those conditions. The unprotected one may well survive several seconds or more in practice.
The only easy to add any kind of protection would probably be some foldback limiting of the supplies, arranged so that any current drawn over the maximum would limit automatically with the rail folding back to a lower level too.
I suspect that there probably isn't an issue for the type of use you have in mind.
My opamp running with very low temperature even with heavy loads like 32 ohm headphones.
I use symmetrical 12V power supply for that chip.
I found something like this.
http://www.8085projects.info/wp-con...rated operational amplifier output._thumb.jpg
It look quite simple.
I use symmetrical 12V power supply for that chip.
I found something like this.
http://www.8085projects.info/wp-con...rated operational amplifier output._thumb.jpg
It look quite simple.
I'm not quite sure how that is meant to work tbh. The FET is self biased ? Never seen anything like that before if I'm honest. How does it detect over current ?
I'm not sure there is some description at this page.
Free Electronic Circuits & 8085 projects Blog Archive Over-current protection circuit with Integrated operational amplifier output Free Electronic Circuits & 8085 projects
Free Electronic Circuits & 8085 projects Blog Archive Over-current protection circuit with Integrated operational amplifier output Free Electronic Circuits & 8085 projects
Thanks 🙂 The description on that site reads like a translation of a translation lol.
I can't see how it can possibly do anything other than not work tbh.
I can't see how it can possibly do anything other than not work tbh.
As most headphones are intended to be driven from about 120 ohms of output impedance (may be less... it depends on the headphones) you can try to use a series resistor connected to each OA output. Surely you'll need to try several values until you find the right one but at least this solution is cheap and almost fool-proof.
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