I've been working on some neat-o projects with a Raspberry Pi 7" Touchscreen on a Raspberry Pi 2 for a few weeks.
But, the Pi has been plagued by the yellow lightning bolt icon, which means "your power supply sucks".
Nothing I've tried, until now, has fixed it. I've been through several phone chargers in 1A, 2.1A, and 2.4A varieties, several USB cables, and I've tried a Pololu 3.5A step-down switching regulator, and my own prototype 3A step-down regulator (I think I broke it?!)
My solution: power the touchscreen and Pi from independent phone chargers, after disconnecting the 5V jumper between them. Hope this helps someone else.
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