I'm trying to power a Raspberry Pi 4 via a 6-AA battery pack via buck converter which steps it down to 5V but it gets stuck in a reboot loop on boot up.
Watching the display on the buck converter, the voltage dips below 4.6V and the red light goes off on the RPI and it reboots again (I only get as far as seeing the rainbow screen and then the 4 raspberries).
I've gone up to 5.3V on the converter but it still dips down too low. I got it to boot fully once on rechargeable batteries and once on alkaline but after that no luck. Once when watching on alkaline it seemed like it didn't dip that time for some reason and then right after when trying it again it did dip. A wall power supply works fine.
What's the best way to solve this? Add a component of some sort or by some other method? Perhaps increasing the voltage above 5.3V if that's safe to do?
The 5V output of the buck converter is going to GPIO pins 2 and 6. In case it matters, the buck converter I'm using is Amazon item B00Q48BRFO.
====UPDATE Oct-14-2020====
Thanks to the helpful answers. The last things I'd like to know are:
- Any there concerns about damaging something by starting the Pi up with the USB power supply and then unplugging it and letting it continue running on the battery pack but at lower power draw since under my intended usage? I.e. is it safe to switch out power like that? I'd have the battery pack -> converter already plugged into the 5v and ground pins on the GPIO and then just pull out the USB power. I understand the Pi may not run for long on batteries given its draw, but that's okay.
- Instead of getting a different converter like Dmitry mentioned may help, is there a capacitor or something (not too knowledgeable on electronics components) that I could stick somewhere to provide for the peak draw on boot up? Since it has worked a couple of times as is, I'm assuming I have just barely not enough to handle, so was hoping this could be an option.