HP Prime G2 die when i turn it off while charging

[dophuc]

Hello everyone,

I have a problem with my HP Prime G2 (2AP18AA). I just received it a few days ago, brand new so this is the first charge. When the device is off, I plug in the charger, the screen lights up and the icon says charging. I saw the screen light so I decided to turn it off (while still plugged in the charger), as soon as I pressed [Shift] + [On] keys to turn off the device, the screen suddenly flashed and there was a small noise with a slight smell burned and the calculator turned off. I immediately unplugged the charging cord, removed the battery and the cover. After removing the lid to look at it, I noticed that one component was burned and had a strong burning smell. I don't understand why it happens because I usually turn off my Ti84 plus CE while charging and nothing happens. Previously I also had HP Prime, version NW280AA, it also died while charging for no reason.
I don't understand how HP Prime can be damaged so easily, it's clearly a hardware or design fault.
According to the information I find out, the burnt component maybe is the A476 tatalum capacitor. Please help, Is my case covered by warranty? if not, where can I find this part to replace the burnt part of my HP Prime G2, will it work again?
Thank you everyone!

[Guenter Schink]

There shouldn't be a problem switching off the calculator while charging. I do that all the time( with G1 and G2). Thus there seems to be a hardware fault.
I can't imagine why this shouldn't be covered by warranty. Here in the EU we'd simply return it to the shop for an exchange. Don't know how that works elsewhere.

Günter

[Kevin Ouellet]

Question: Before charging it for the first time, did you let the calculator reach zero battery percentage to the point where the device turns off by itself? I remember reading stories about how it was a bad idea to do so with any device that has a rechargeable battery (other than AAA's), especially older phones, and that it could also reduce the battery lifespan and even cause the battery to explode and catch fire, but I don't remember if letting a device get to 0% or worse letting it sit at 0% for weeks can cause hardware damage during the next charge. Does the HP Prime G2 have any protection against such scenarios?

[Beatskip]

(03-23-2022 05:54 PM)Kevin Ouellet Wrote:  Question: Before charging it for the first time, did you let the calculator reach zero battery percentage to the point where the device turns off by itself? I remember reading stories about how it was a bad idea to do so with any device that has a rechargeable battery (other than AAA's), especially older phones, and that it could also reduce the battery lifespan and even cause the battery to explode and catch fire, but I don't remember if letting a device get to 0% or worse letting it sit at 0% for weeks can cause hardware damage during the next charge. Does the HP Prime G2 have any protection against such scenarios?

No, this is pure and simply a matter of defective hardware. It's shitty, but even with the stringent of QC in any process, faults happen. Any modern (advanced) device utilising lipo's has a proper battery management IC that protects the battery from over- and undercharge scenarios.
AFAIK the shutdown of the device is completely handled by the Processor (so actually it never actually shuts down, more 'goes to sleep'). So shutting down the device during charging simply can't result into what is described here, a faulty ic, faulty charger or even spikes on your mains lines most definitely can cause this. So my advice, return your device to the shop, you should get a new one. And check your USB charger, if it's even slightly chinsy, throw it out. The 5 bucks you saved by buying a shitty one, you just wasted with your device burnt. (note, not blaming you per se, hardware fault of your calculator is most definitely possible. And even if it wasn't, the calc should be designed to handle unexpected spikes in voltage etc.)

[dophuc]

Have a nice day everyone,

I'm feeling happy because my HP Prime G2 has been fixed
After looking up the specs of the damaged capacitor I got a 47uF capacitance (A476), voltage unknown because I don't have the HP prime G2 datasheet. Compared the boards of the two versions of HP prime that I have and found that in version 2AP18AA there are several places where A476 capacitors are used, on the circuit board of NW280AA version there are also a few capacitors printed on the label as "47 10V ". They are not of the same brand but may have similar functions and specifications . So I tried replacing the 47 10V capacitor from the old board to the new one. Good thing that brought the HP prime G2 back to life .
Now it is working and charging normally :calc: .
I will not turn off my HP prime G2 while charging again even though there are some 47 10V capacitors on board NW280AA

[KlaasKuperus]

Hi,

This seems indeed a HW defective. As Kevin wrote, even with an extensive quality check, things like this can happen. Please contact your reseller and ask them to file it for a return. Should be no issue, assuming it was bought not longer than 2 years ago.

[landim]

Hello Guys. I don't know should if reactivate this topic, but, my problem is similar. I have a NW280AA HP prime model. A Long time ago, I didn't have the charger original, and I used the turbo chager from my smartphone to charge the calculator. So, I did forget this on the plug, and when I remove the calculator of the charge, the temp was very high and didn't power on. I disassembled the calculator, and looked for the U302 and U306, this chips were burned. Someone can help me? I need the code of this chips for purchase and replace them. My english is just a little, sorry for wrongs.