Looking for help finding a sci fi series

I'm trying to remember the author/title of a series of books I read about 15 years ago.

In the books, humans in the distant future are sort of loose nomadic groups with some high tech, but not much civilization. I remember at least one character was killed by some sort of fungal infection that was fairly rapid. Additionally, I think there is a scene where a character falls through the center of a planet.

I know that's a jumbled mess, but I'm hoping some of it rings a bell for someone. I mostly remember the chargers fleeing from something.

Thanks in advance!