TI community,
I have an audio design problem I hope someone can help with.
I have a jfet preamp / buffer that uses either +48v DC phantom power or 18V battery power from 2 9v PP3 batteries in series. Everything works beautifully unless two batteries are used that have different voltages (or types). In that scenario one battery heats up a great deal. It is hot enough to present a potential fire and/or burn hazard.
Is there a simple passive solution to prevent one battery from attempting to charge another in a series configuration?
I will lose a good bit of headroom running the preamp at 9V when on battery power, but If I can't remove the heat problem from the design It will be necessary.
If necessary to allow advanced users to use 18V, I can possibly include instructions to use the single 9V battery clip across 2 batteries, and add a second clip with the leads soldered together and insulated to create the series connection, with a strong warning, voided warranty, and disclaimer to indemnify the company from damages.
Has anyone seen this type of heat problem, and perhaps found a simple solution that I may be overlooking?
Without a doubt, some customer will grab 2 random batteries and clip them in and ignoring all warnings
.... create a very big ( and potentially litigious) problem.
Many thanks!
