USB Ports, Adapters

jerseyjim wrote:
Gee....things is so complicated now.Why? I have my Belkin 4 USB port adapter into one laptop USB....my wireless mouse into another and my hardwired keyboard into the third. All work fine. My cell phone came with a house charger...and I bought a 12V charger for the car/motorhome. My Tablet has it's own house charger...2.0, 3.0 (for speed?) USB ports and colors? Don't know. Everything works fine. Of course I use this laptop strictly for pleasure...not business.
Maybe I compartmentalize too much...........

I would tend to aggree with your point.

But for some strange odd reason, folks seem to think a PC should charge a cellphone and tablet..

Cellphones and tablets come with their own wall chargers AND with a simple high current 12V cig to USB charger can easily charge directly from a 12V battery.

Modern cellphones and tablets are able to "adapt" to the max charging current of a computer USB port but in doing so will take forever to charge those devices.

The reason.. Well smart cellphones and tablets ARE designed to charge the fastest with 2A-2.4A at 5V.

Plugging a cellphone or tablet into a PC USB port will result in only charging at a max rate of 500 ma, This results in a charge time of at least if not more than 5 times longer than if you used to proper 2.4A charger.

So if your cellphone or tablet took 2hrs to charge with the proper 2.4A charger it will take 10 or more hrs to charge with a 500 ma USB port.

Computer USB ports were NEVER designed to be a "charger" for cellphones or tablets..

By the way, you CAN "blow out" the 5V part of a computer USB port.. Pretty much TRASHES that port and if your laptop has one USB port you now have a door stop. A PC USB port is a rather expensive charger..

Buy the proper 12V to USB charger for those devices, you can get 2.4A 12V to 5V USB charger for $5 now days..