We've been using these ESP07 modules and have had a few problems with them. To avoid another step in production we're just using the standard AI Thinker firmware which is good enough. However, I've come across a few now that seem to lose their memory. They're tested working fine and then sometimes they don't boot... and once this has happened it won't work again until it's been re-flashed. They're likely to have been browned out. It's sort of repeatable if we slowly bring the power up.
Has anyone come across this. Is there a way to protect the flash memory?
They're still working as they attached to the router and the boot loader output works but the AT commands don't work.