I bought a nice Xiaomi 10Ah power bank. It powers up a Chromecast Audio puck almost forever. But I planned to use it mostly for a RPi 3B+ with Allo Boss DAC running Moode to have a Spotify Connect device with high quality output. The problem is, the RPi does not start when the power bank is connected.
I found out, that it will start booting, when I connect the power bank to the chager - then it is most probably powered from the PSU - because when I disconnect the PSU, it will turn off briefly and then it will start from the power bank.
What could be the issue? Maybe voltage output from the power bank while the RPi is connected? This is a 2.5 A power bank, there should not be a problem with current capacity.
Any tips or comments from users powering their RPi from a power bank will be appreciated.
I found out, that it will start booting, when I connect the power bank to the chager - then it is most probably powered from the PSU - because when I disconnect the PSU, it will turn off briefly and then it will start from the power bank.
What could be the issue? Maybe voltage output from the power bank while the RPi is connected? This is a 2.5 A power bank, there should not be a problem with current capacity.
Any tips or comments from users powering their RPi from a power bank will be appreciated.
So then the RPi does start from the battery. It just stops working when you switch from mains power to battery power. I guess the electronics in the power bank takes a moment to do the switch, and the RPi is left without power during that time.
It is nice specs and it works perfectly just about for everything but the RPi. So I wonder why and if there is another solution than buying a new one dedicated for the RPi - I will try loading the second USB with a phone or something. It might also be some kind of soft start, that the RPI does not detect the power up.
mbrennwa: It does not start, when I connect it directly to battery only. I need to connect it to the RPi, then to the charger. When I remove the charger, the RPi powers of for a short time and then it starts already on the battery only.
mbrennwa: It does not start, when I connect it directly to battery only. I need to connect it to the RPi, then to the charger. When I remove the charger, the RPi powers of for a short time and then it starts already on the battery only.
Inside power bank is step up converter ic, it converts 4v into 5v. So in your case it need part of a second to stabilize after connect disconnect charger. it is better to use 8v pack and regulate to 5v because bower bank is very noisy when you connect it to the scope and measure. Try to put 1F on rpi input, can help a little bit with miliseconds disturbances on power line.
Use a better usb cable.
If the usb cable ,between power bank and RPI is a thin wire ,you will have high voltage loss due to high current.
I found with two different portable chargers aka power banks that they need to see a certain amount of load to continue supplying charge. I thought I would be able to run a small USB powered LED lamp from them, but one shuts down after 30 seconds, and the other shuts down after one minute, so this LED lamp is not enough load to keep the ‘smart’ chargers going....
Part of the issue may be that the Pi requires an input voltage darned close to 5V and it can draw significant current. The comment about using a better cable between the power bank and the Pi is also valid. I also would not expect the 5V output to stay at that level when switching between charging and not charging.
You can get a walwart for less than $10 for the Pi. If that works, then you can conclude the battery is not sufficient for the Pi. The Pi with HAT will require a certain voltage and amperage at startup, and while the specs of the battery may sound sufficient, in reality they may not be doing the job.
Anderssonix: I was talking about mine, I tried yesterday.
jhofland:Good points. No cable worked
dtaylo3: The Pi works normally with a wallwart. Good point with the DAC, maybe it is the super capacitor that draws the current at startup.
In any case, I need the DAC working from battery, so I will separate the DAC supply and try again (need USB-C cable for that). A linear battery supply is a future way to go anyway.
jhofland:Good points. No cable worked
dtaylo3: The Pi works normally with a wallwart. Good point with the DAC, maybe it is the super capacitor that draws the current at startup.
In any case, I need the DAC working from battery, so I will separate the DAC supply and try again (need USB-C cable for that). A linear battery supply is a future way to go anyway.
The RPi draws a much higher current at startup and this at least prevents mine starting up with many PSUs that are easily big enough to supply the current for normal operation. It took me a while to realise that if you connect the RPi to a monitor you'll see an "undervoltage" symbol on the screen if the PSu is not powerful enough to handle the startup spike.
No, nothing is overloaded and does not shut down.
If you use a simple USB cable, the powerbank allows only a low current mode (mostly only 500ma-1A). This is by far not enough for the Pi3. You need to trigger the high current mode to start the Pi from the bank. Often the powerbank needs 2,5V on D+ and D- pins to trigger the high current mode. Its differs from one manufacturer to another.
If you use a simple USB cable, the powerbank allows only a low current mode (mostly only 500ma-1A). This is by far not enough for the Pi3. You need to trigger the high current mode to start the Pi from the bank. Often the powerbank needs 2,5V on D+ and D- pins to trigger the high current mode. Its differs from one manufacturer to another.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.