This is a follow-up to this thread: https://arstechnica.com/civis/threa...-polarity-of-this-laptop-barrel-jack.1491071/tl;dr I have a laptop but no charger, and I'm ...

This is a 5V to 12V DC-DC step-up (boost) converter circuitry that is especially ideal for the USB powered applications. First of all a USB port has two current supply modes. Before detecting the ...

Using this circuit we can convert 5V DC from the computer USB port to 12V DC and a circuit like this will find a lot of application in USB powered systems. The heart of this circuit is IC LT1618 which ...

There are very few things as annoying as your phone battery draining in the middle of a drive, especially when you need it to find your way around. You reach across for your power bank, only to ...

Most modern cars offer at least two ways to charge up a smartphone, in the form of a 12V lighter socket and a USB port. The latter could be more convenient for many, as it uses the same cable you ...