Hi,
I am using a Raspberry Pico to read ADC voltages. I find when using a USB power supply, the reference voltage is unstable, but when plugging it into a laptop, it is fine.
Is there a battery pack that can be plugged in 24/7 and power the Pico?
ie Power supply feed the battery, battery feeds the Pico.
Thank you kindly.
Will the battery holder below work as required? The issue with powerbanks I have tried is that they will cut out after ~20s as the power draw is too small.
Hi Sanny
This issue about using Power “Banks” as Power “Supplies” has come up many times so am not going into it again.
Is by any chance the Power “Supply” you are using that you say is unstable really a Phone charger. The same thing applies, there is no reason for a charger to be particularly stable. The Laptop USB port will be a nicely regulated 5V supply and that is where ypu are noticing the difference.
The short answer would be YES. With the added advantage that is rechargeable (with a slightly unstable “charger”). Be a bit careful and purchase a flat ended battery which is 65mm long (I believe Core only stock such batteries). The self protected and other nipple types can be up to 70mm long (still branded 18650) and will struggle to fit into most holders, this one included.
Cheers Bob
Hi @Sanny,
The 2-Way 18650 Battery Holder won’t work for this use case. It doesn’t output power while it is being charged.
It also has an auto-off at 120mA or 40mA depending on the mode which the pico power consumption may fall below so you may run into the same issues.
There are UPS Modules available for The Pico but you may run into similar issues. Most UPS systems I know will only switch over to battery once the power in is cut.
You may still run into the unstable voltage issue in this case.
Hi Aaron
I just had a read and didn’t find anything about this little gem.
Not very useful then is it. This then becomes just another small power bank with the same shut down characteristics. I must apologise for not researching before posting. Getting a bit lazy in my twilight years.
The only advantage this has is the number of outputs so maybe if you are using a few you might make it past the 40mA. But there again you only have a small capacity. Remembering that any capacity quoted is AT THE BATTERY, NOT at 5V
A bit useless if you are trying to power CMos or other very high impedance devices.
Cheers Bob
I’ve already made note of this internally and we are updating the product page as we speak.
We had updated the information on the 4-way version when we found out about this but the 2 and 1-way didn’t get the additional information.
@Sanny This is the type of device you need, but it is rather expensive.
Search for UPS as it will provide seamless power transition.
Cheers
Jim
EDIT: This one is for the Pico, it says.
Keep in mind that an UPS is designed to provide battery power when the mains supply is down. It is difficult to design a battery charging system that supplies battery power at the same time it is charging the battery. Current flows one way at a time, into a battery or out of it.
Hi James
“Expensive” depends on how bad you need it and how much quality you are prepared to buy.
Alas I think that too often a project or experiment throws up problems if trying to get a result “on the cheap” as the saying goes.
True when you only consider the battery. But when the battery is a back up source as in UPS the primary power has to operate the load equipment whatever that may be AND replenish the battery if it has been used. If the primary source will only do one of these tasks the battery will eventually go flat and the system has to shut down until the battery has charged. I think some forget this bit of extra when sizing a power supply and find themselves with problems.
That is one reason I try to get people to work out what they think the power requirement will be then double it when selecting a power supply. Less problems that way.
When you are considering currents at a junction like the junction of battery, load and primary supply Mr Kirschoff has it in one when he says the currents into and out of a junction MUST add up to Zero.
So when you consider the above junction with a load say of 1A and a battery replenishment requirement of 0.5A that is 1.5A “leaving” the junction thus there must be 1.5A “arriving” at the junction which is what the primary supply has to provide at that time.
All Swahili a bit but not too hard when you think about it.
Cheers Bob
Hi there,
Wondering if this UPS can supply power to a Pi5 whilst being charged at the same time through the USB-C input on the UPS?
Kind regards,
Andrew.
Hi @Andrew198398, Welcome to the forums!!!
The board can charge the batteries while also powering the Pi 5 over the USB C connector on the UPS HAT.
If the Pi is using a lot of power the charge rate of the batteries will likely drop or even stop.
Just so you know. this board doesn’t have any hardware Over-Discharge protection for the batteries. The software package that runs on the Pi can shutdown the Pi when the voltage gets low but if it isn’t installed then it will take batteries down to 2.4V.
Had a friend get this board and do a battery runtime test without knowing about the software package. It lasted 6 Hours 30 minutes before the Pi died at 2.43V per cell.
Thanks Aaron,
Much appreciated.
What’s the name of this software package?
Is it automatically installed on Pi OS?
I’m using a Pi 5 running Pi OS lite but happy to install any supporting packages required.
Do you know if there are any other boards with over-discharge protection? Seems like an oversight on this one?
Cheers, Andrew.
Hi @Andrew198398,
The wiki for this product has a few tutorials included for setting up those parameters. You can find them here or alternatively, this wiki from the manufacturer goes into a fair bit more detail with the setup instructions and I found it to be more informative.
If you are after the software to manage these settings specifically, it can be found here.
I’m not sure of an alternative to this board at the moment that has over-discharge protection built into the board but hopefully, someone else can weigh in with a decent alternative.
Hope this helps!
Thanks Samuel,
Those resources are much appreciated!
I’ll purchase one and give it a shot!
Cheers,
Andrew.
Sounds good Andrew!
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