Am I picking the correct car charger for my laptop? - Page 1
Forum section: electronics / general

author: Faranight
author_rank: Unknown
timestamp: February 26, 2025, 10:00:17 am
content: Hello, I was originally going to ask this on the BleepingComputer forum, but I got locked out of the forum (Thanks, Clownflare! Your moments usually take an eternity).Anyway, I have a small Asus Notebook UX410U that I use for various things. I sometimes go outdoors on travels and bring this laptop along, but unfortunately its use is limited by the battery life. I'd occasionally like to use it for prolonged periods, so I'll need a way to recharge it on the go. I thought about purchasing a car charger, which would be able to power the device from a 12V car battery. I have an original outlet mains charger, but I'd rather avoid having to use it in combination with an additional inverter. A second adapter that can plug into the car's 12V socket and charge the device directly would be preferable. Sadly, this subject is very much new to me, and I'm not completely sure which charger to pick or what to pay attention to when buying, so I'd just like to verify before I buy.Some things that come to mind are:The first thing I noticed is the DC power jack shape, which obviously has to match the socket that it is being plugged into. It must also have the correct polarity (center-positive). At first I was searching for a charger with a matching socket, but then I noticed that some chargers on sale offer different plug adapters (see link below). I kind of like the idea of being able to use a single charger on multiple devices.The second thing that comes to mind is the charger output voltage and power. My original ASUS mains charger has a sticker that says "OUTPUT: 19V 2.37A". Does the new charger have to output this exact voltage or is it OK, if the output voltage varies? If so, by how much? What about the rated amperage?I noticed that some car chargers on Amazon are advertised as "universal chargers", but I'm not completely convinced just yet. How do they know what voltage to output, and that the given voltage doesn't exceed the device's max voltage rating? How does this work? The only way I can think of is that the plug adapters that are connected to the end of the output cable are somehow communicating back to the charger (i.e. via a resistor and a 3rd wire) what voltage to output.I've been looking at this device. Will this device work for me?https://www.amazon.de/-/en/Universal-Charging-Adapter-Pavilion-Vivobook-black/dp/B0CF54WKQJThanks in advance.

author: Halcyon
author_rank: Unknown
timestamp: February 26, 2025, 10:48:42 am
content: Why not just grab a 12v to 230v inverter and use the existing power supply?

author: Faranight
author_rank: Unknown
timestamp: February 26, 2025, 11:07:34 am
content: Quote from: Halcyon on February 26, 2025, 10:48:42 amQuote from: Faranight on February 26, 2025, 10:00:17 amHigher costLower efficiencyTwo devices instead of one

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 27, 2025, 04:32:56 am
content: Get a USB-C car charger rated for at least 100W on a single port (that guarantees it can output 20V, which lesser ones often cannot) and an adapter to convert the USB-C to the charging plug if charging from USB-C is not supported.

author: Faranight
author_rank: Unknown
timestamp: March 06, 2025, 11:29:38 am
content: Just a quick update, I risk-bought the Amazon charger that I linked in the first post, and it works fine!