Updating battery power supplies to 2017

Searching for DIY battery 48v supplies here didn't get me much.

The most recent thread I could find was from 2013, and things did go on on DC-DC chips

Hasn't anybody made a new DIY project for a battery powered, DC-DC, 48v power supply?

Thanks!

I'm not sure why you would want to do that in 2017, but the customer is always right.. ;D

You want to use a "boost" converter to step up the output voltage.  Keep in mind that a 9V battery stepped up to 48V will discharge the battery at more than 5x the microphone current draw.  A typical 9V battery holds something like 250 mAh when new, so you do the math.

This sounds like an interesting project to learn on. Look for application notes from switching controller IC makers, that generally offer lots of good "how to" advice.

JR

Well, this hasn't been an issue for a long time, as I always power the mics from my mixer or my XLR-3 inputs camera.

But this time the camera has only 1/8" dreadful inputs, so I better have that as an option too. Rare application, but possible.,

Can you be more specific on where to look for ideas for this?

Some time ago, when I designed a portable mixer, I had to use a DC-DC supply, solved with a not made anymore chip. Also tried an LT chip, but it was noisier. Even if I still have some assembled boards around, it might be interesting to see how small I can get it.

About the battery discharge, and considering a 10mA discharge, my math gives me 5 hours at least. Probably more, because I think this mic is less current hungry. 

Unless you have some desire to learn about dc-dc switching supplies, you may be able to accomplish what you need by stacking up a couple 9V batteries.

At Peavey we sold an accessory that was just a single 9V battery phantom supply and it worked with many mics.

If you are going to be using your own mics in a controlled situation there may be an easier way...(batteries, try it and see how much voltage you actually need).

If I was set on doing a switcher I would look at digikey or mouser components and look for DC-DC switching regulators... you will need to add an inductor and a few parts. For more options look for a controller chip that will require you provide the switching device too (the regulators have the switching device built in).

http://www.ti.com/lit/ds/symlink/tps55332-q1.pdf  here is an example of one option, while I did not perform an exhaustive search or look for cheaper options.

Read the data sheet application note for a quick tutorial about switching supplies.

JR