Hello, I've been told the following and I was just wondering if someone can confirm how accurate it is?
If I purchased a phone that came with a 5V 2A power supply, it would be safe for me to use one rated at 5V 0.7A. I have been told that when the phone tries to draw more than 0.7A the voltage will drop, the phone will detect this and won't try to draw any more? (I know USB provides ways for power supplies to communicate what they can deliver, but I don't think many cheap, stand alone chargers do this, and just act as a regular power supply.)
This isn't true though for laptops though as they aren't expected to use different chargers unlike phones. If I used a different power supply with a lower maximum current than the one provided with the laptop, either the power supply's voltage would drop and the laptop won't be able to draw the current it needs, or the power supply will maintain its voltage and try provide a higher current than it was designed to, potentially damaging the supply.
On a fairly basic level, how accurate is the above?
Thanks.
Edit - This is all theory, I'm not actually wanting to do any of the above!
If I purchased a phone that came with a 5V 2A power supply, it would be safe for me to use one rated at 5V 0.7A. I have been told that when the phone tries to draw more than 0.7A the voltage will drop, the phone will detect this and won't try to draw any more? (I know USB provides ways for power supplies to communicate what they can deliver, but I don't think many cheap, stand alone chargers do this, and just act as a regular power supply.)
This isn't true though for laptops though as they aren't expected to use different chargers unlike phones. If I used a different power supply with a lower maximum current than the one provided with the laptop, either the power supply's voltage would drop and the laptop won't be able to draw the current it needs, or the power supply will maintain its voltage and try provide a higher current than it was designed to, potentially damaging the supply.
On a fairly basic level, how accurate is the above?
Thanks.
Edit - This is all theory, I'm not actually wanting to do any of the above!
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