[Solved] Battery issues

I need to get to bed, I have a long day tomorrow.

I will ask Daniel for any ideas. Do not leave the Pokitto into charge over the night (there should be no issue, theres a built in protection circuit, but lets just play it safe here). I’ll try to think of something to try - but like I said this is the first of this kind of issue that I’ve come across.

Even if there is something wrong you can relax because we will reship a board if that is the case. Every single broken Pokitto has been replaced so far, nobody has been left in trouble.

1 Like

Well, it does now. I reassemble it completly and it boots again. But it lasts about 10 second starting squiddy then it just blacks out. It does seems like a power issue somehow. Every restart after that is shorter.

suggestion : i keep it on the charger longer to see if it lasts longer the next few days.

just one question : could you tell me how the charge led should behave ?

Yep, thats a clear sign of power issue

It glows yellow and goes off when the charge is full

What does the blue power led say?

When turned on, it glows blue and as the lcd turns black the led slowly turns off.

1 Like

Ok. Clearly a power issue. It seems your Li-po has “forgotten” its a battery.

Try charging & and drain by turning on, then charging again and drain by turning on. Repeat this cycle a couple of times. I am not kidding: i have seen li-pos “wake up” in this way. This kind of a thing can occur if the li-po charge has gotten really low at some point.

1 Like

Ok, i will try. result coming to you tomorrow thanx for the help sofar :wink:

2 Likes

Had a discussion with Daniel. 4.2V indicates the cell is OK.

  1. It is possible there is a failure on the LDO chip (the main voltage regulator)
  2. It is possible that the cell has a faulty protection circuit - meaning its reading too early that the cell is full and is “blocking” the charge for the sake of safety - its doing its job too well!

We will get back to this tomorrow.

1 Like

I’m glad to see this kind of action being taken.
I’ve known some other discourse-based places where moderators are reluctant to move things that are going off-piste.


We now return you to your regularly scheduled programming.

ok, so before going to work today i did a quick test.

It was on the charger the entire night, the yellow charger led was still glowing softly when i detached it.
It turns on and i kan acces crp-state, however after a few minutes it blacks out again. The speaker gives a soft buzzing sound as the power slowly fails and keeps doing this for about 10 sec.

Put the charger on and the Yellow charge led lights up brightly for 2 minutes than goes back to a soft glow. (like on picture above)

I will cycle trough charging and discharge this afternoon to see if it lasts longer.

2 Likes

The absolute test is this:

  • desolder battery leads (take care terminals do not cross)
  • connect with USB to PC, power on to CRP mode
  • if the problem is battery, it will now work and the charge light will be blinking fast (missing battery)
  • if the problem is the PCB then you will not be able to connect to PC
1 Like

I just did desolder the battery and connected it to the usb.
First response of device was indeed a blinking orange led.
Turning it on into crp state works and stays up. Although it doesnt seem to be very stable, windows has trouble keeping it connected.

Booting into loa.der works but power drops returns then drops again. After a couple of cycles of that i am able to play squiddy.

I did a few reboots and if i power it up now it stays on, no blackouts. Is the usb power enough to run the device at 100 % cpu speed+sound ?

edit: i am measuring charging current(battery resoldered), this is really low at 0.06 A as long as the charge led is really bright. this last few seconds then the led turns off almost completly and power drops to 0.000 A (so not charging anymore)

edit2 : device doesnt turn on anymore…:neutral_face:

I confirm thats a broken protection circuit in your battery. It is the first we have encountered, congratulations!

You are the lucky winner of a replacement battery. Since batteries can not be sent separately, you’re getting it soldered to a pcb & fixed to a case.

1 Like

Well, lucky me :blush:

So the record for Armegeddons hi-score stays intact a little longer :wink:

1 Like

Yes, but it is not stable. What the battery does is smooth out the power generated by the charging circuit.

I understand, it is bassicly buffering power.

Small update, just for the info.

I removed the battery and the device can boot in both states. But depending on wich software is loaded it will blackout because of the power used. The Armageddon game seems to ask a lot of the cpu, combined with the sounds this is to much for the supplied usb power. Other games seem to work but do blackout randomly. As far i tested it will not blackout in CRP state, most likely the cpu load is very small.

I did notice something else and i am not sure if this is even possible but the sound is better ??
It is louder and is there is less crackling.

It’s possible and entirely logical. Your battery was faulty and constantly in low charge. Amplification of sound takes a lot of power. Power is the function of voltage x current. If power exceeds the maximum output available from the battery, the voltage drops. It is exactly if you had a big pipe leading water from a small reservoir (depleted battery). A big pipe and little water means systemic pressure (=voltage) collapses. And that collapse means? Crackling sound and low volume.

2 Likes

Replacement battery+board arrived today, after charging it works fine. Thank you for the support!

2 Likes