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Supercap charging circuit for RTC backup on STM32

The STM32G070CB/KB/RB datasheet chapter 3.7.6 VBAT operation writes: "An internal circuit for charging the battery on VBAT pin can be activated if the VDD voltage is within a valid range." ...
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Solve this puzzle: Car lighter port blowing phone battery

It sounds like the effects of a load dump or a reverse battery jump. Disconnecting a cable from a weak or bad battery while is charging by the alternator will generate a massive load dump. I would ...
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1 vote

Solve this puzzle: Car lighter port blowing phone battery

This sounds more like a failure of the alternator/voltage regulator system in your Jeep, causing voltage spikes above the acceptable ~12V to ~14V range. You can test this with a voltmeter that has a ...
  • 3,290
2 votes

Solve this puzzle: Car lighter port blowing phone battery

The lighter port is a 12V high current source. I speculate that it is difficult to break. To use it to charge a phone, there must be a 12V to 5V adapter (USB style??). The charging adapter is ...
  • 3,344
2 votes

Battery balance circuit gives zero volts at output

I figured it out, there is that weird thing about some BMS modules that they need initial charging, even for just one moment, to start operating. Basically BMS comes off dead and you wake it up by ...
2 votes

Can a 9.6V Ni-MH battery be charged by unregulated 9V adaptor with 13.5V output?

If I've correctly read the resistor colour-code as brown, black, black, black then it appears to be a 100 Ω current-limiting resistor. This would limit the current to \$ \frac {13.5 - 9.6}{100} = 39 \ ...
  • 163k
1 vote

Reverse engineering: Why is there a PD IC in this Adapter?

This adapter does three things: Power routing through, from Type-C Receptacle to Type-C plug, USB2 data passthrough from Type-C Receptacle to Type-C plug, Thunderbolt-3 alternate mode with a TB3 ...
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3 votes
Accepted

Does peak mains power consumption of a laptop chargers depend on input or output parameters?

Given that I have ~230V in the mains, does that mean that at the peak load the charger would pull whole 575W from the mains (with ECE as low as 22.7%)? No. The 2.5 A are just a worst case, "...

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