Breadboard-able +/- 5V power supply that can do 100s of mA?

Hello! I’m getting into some DIY video bendy ideas. I want to play with a LMH6574 or AD8184 multiplexer, but it seems that these IC’s want to have a proper split rail power supply. I want to be able to plug a small camera into this circuit as well. The camera requires around 50mA of current at >7V.

The basic idea is to do camera->input buffer stage as given by the LZX Interface Examples->comparator->multiplexer to make a very simple/lofi luma keyer.

It seems like I should be able to take 10V off of my bench supply and do something to create +/-5V rails with a common GND in the middle. I could then have a separate power regulator that’s 0-7V for the camera, and connect that supply’s 0V to the virtual GND in the middle of the split rail supply.

I am familiar with the old “voltage divider to unity gain buffer” method of generating a virtual ground in the middle of a wider voltage swing. But, the op amps that I have for the unity gain buffer can only source/sink like 20mA. So I am worried about driving the camera with this virtual GND. I’ve been researching and it seems that making higher current split rail supply is…challenging! Am I considering this problem correctly, or are there any tips on how to do this in a straightforward kind of way?

Thank you! I haven’t had to deal with split rails before.

There are quite a few non-smd DC/DC converters that will just “do this” for you, but you’re getting yourself into a whole world of potential problems when you bring a switching converter into the mix. One of the most straightforward ways to generate a split rail is to use a pair of complementary linear regulators such as LM7805+LM7905. Input rail of +15-24VDC along with your virtual GND topology, some load resistors, and the regulator pair should get you a pretty serviceable split rail breadboard supply.

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Thanks! I just looked up the application circuits and ordered some 7905’s.

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