Laptop power supply lower voltage
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Here is the answer to this question, after I did some research/searching. The laptop power requirement is determined during design. In my case, my laptop's requirement is 19.2V/3.95A. But why does battery voltage is 10.8V or 11.1V? It is because every battery consist of some 18650 dry cell battery which its voltage is 3.6V or 3.7V. Three batteries are arranged in series to produce 10.8V or 11.1V (3.6*3=10.8V, 3.7V*3=11.1V). As the laptop power requirement is 19.2V*3.95A (=75.84 watt), then the charger must be made according to that spec. How about the power from the battery? Need boost converter to convert the 10.8V to 19.2V. And that is inside the laptop or battery. What about the cell battery is not 3.6V? Say if you can increase the voltage to be 10.4V like 9V dry cell 6LR641, and each two of them you arrange in series and then you parallel to another two series, then you will get voltage 20.8V. To meet the 19.2V you need to step the voltage down, also converter but to step down (rather then to step up). So, when we plug that 19.2 charger to a laptop with a common battery we have (10.8V), then the voltage from the charger need to be stepped down inside the battery. Vice versa, when laptop is taking power from the battery, it need to be stepped up to 19.2V
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So I'm on vacation. The car ride is very long, and like watching downloaded movies on my Chromebook to pass time. It has excellent battery life and can last the full nine-hour car trip, but I want to able to charge it in case I want to start streaming. I know they sell car charger to wall outlet converters so I plug in my stock charger, but I really don't want a string of dongles that I have to manage. I've found USB to 5.5mm cords on Amazon but I can't find any that output the 19V that I need.
So my question... Can I safely charge my laptop using a cord that outputs less voltage than what is normally used to charge my laptop? I'm not looking to be able to charge it as fast, or even faster than I'm using it. I'm just wondering if it will add a couple hours of use to my laptop, or damage it.
Laptop: TOSHIBA Chromebook CB30-C/CB35-C.
Charger: 100-240V~1.2A (input) ---> 19V=2.37A (output)
Cord: USB to 5.5 mm/2.1 mm 5V Barrel Jack
Needs to be close to 19V. 18-20V likely fine. You might get away with 15V. 5V is very unlikely to work.
You won't get one fed from USB; there just isn't enough power. You should be able to find one fed directly from a 12V cigarette lighter plug, though.
Needs to be close to 19V. 18-20V likely fine. You might get away with 15V. 5V is very unlikely to work.
You won't get one fed from USB; there just isn't enough power. You should be able to find one fed directly from a 12V cigarette lighter plug, though.
You can think of voltage as pressure. You need 19. Anything below that won't be sufficient to reach the pressure to pump anything into the battery. Most car systems are 12 volts. So one way or another you need to electrically step that 12V up to 19V. USB provides 5V electricity and it can't supply the power you'll need to step it up to what you need. The device you plug into a car to power a typical wall outlet is called an inverter. It converts the 12V DC car electricity into 120V AC electricity. You can then used your regular wall outlet charger to change that 120V AC electricity to 19V DC electricity to charge the laptop.
Edit: Just saw your Amazon post. Yes, that will do it also. It's made for the purpose.
Edit: Just saw your Amazon post. Yes, that will do it also. It's made for the purpose. Thanks! I ordered it! I like your analogy for voltage btw. Status Not open for further replies.
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