I'm powering my circuit from 5V USB. Since USB is already regulated, I don't need a voltage regulator.
Will adding a modern regulator like L78M05C offer protection (besides regulation)? Concerns:
- Short circuit - The datasheet says it protects against this. (Is it needed? Won't any USB source have this?)
- Reverse voltage - I can't tell if the L78M provides it; this post suggests modern regulators do. The L78M datasheet doesn't seem to have any info about this either way, but does say "Each type employs internal current limiting, thermal shutdown and safe area protection, resulting it essentially indestructible" (emphasis added). If that doesn't include reverse polarity protection, what does it include?
- Current limiting (an auto-resetable fuse) - the reg. provides it, according to the data sheet. Is it needed for a USB source? (Sources may be cheap knock-off chargers.)
- What other protections should I have? I want to protect both my circuit but more importantly the USB source, and, since I'm a neophyte, I have to anticipate design and construction errors.