Laptop chargers can be fairly bulky and unwieldy, at odds with the supposed portability of their devices. A group of MIT graduates has recognized this and developed a charger that is significantly more compact. The Finsix Dart is about a quarter of the size of other laptop chargers.
Finsix was founded in 2010 with plans to miniaturize the bulky chargers for all sorts of electronics. The laptop charger market was the first area in which the Finsix team thought it could make a worthwhile difference and in which it thought it could gain traction.
After four years of development, the team launched on Kickstarter to raise funds for production of the Dart charger on April 14th. The company reached its US$200,000 goal in just 12 hours and is well on its way to doubling that figure by the end of the campaign.
Finsix says that the Dart is, "the world’s smallest, lightest laptop adapter." It provides 65 W of power and works with inputs of 90-265 V, connecting via charger port or via USB for other devices. The charger takes up just 2.5 cubic inches (6.35 cubic cm) and it weighs 60 g (2.1 oz), with a 6 ft (1.8 m) power cable. According to the company, the Dart will work with most PC laptops and will work internationally. Dart for MacBook and Custom Dart models are also available.
Finsix says it has been able to reduce the size of the charger by increasing the speed of the switching cycle and minimizing the amount of energy lost. "Switching isn’t a perfect process and during every cycle some energy is wasted in the form of heat," the company explains. "At Finsix, our technology allows us to waste far less energy with each cycle. Thus, we can cycle up to 1000x faster without wasting any more energy than a conventional power converter. Cycling faster means we can transfer a smaller packet of energy to each cycle – and make the power converter a lot smaller."
Those wanting a Dart charger can make a pledge on Kickstarter, starting at $89. Alternatively, the device will be exhibited at CES 2015 in January, with commercially availability expected some time after that.
You can watch the Dart's Kickstarter pitch video below.
Sources: Finsix, Kickstarter
So it looks like they designed a bridge rectifier (diode bridge) that runs at higher frequency providing a smoother output and thus can use a smaller capacitor etc.
So I think the circuit would look something like: AC > bridge rectifier > DC > capacitor > voltage regulator
I can understand the reduced size from increasing the frequency of the rectifier without blocking but wouldn't other stages (like the voltage regulator) still produce heat in mostly the same way as a traditional power supply? The only thing I can think of is maybe with a more stable current into the capacitor the voltage regulator on the other side doesn't work as hard either.
If that's true the technology has a lot of potential outside of just power adapter but since so many electronics have different adapters and requirements they would probably have to license out the technology. For me both my laptops are over 65W so I wouldn't be able to use the Dart.
Buy a MacBook...
I recon the only invention here is combining vibrant colors with a charger, but I might be wrong though. I mean TI has about 100 billion dollars and they are in the SMPS business. I seriously doubt that some students can just beat their ass in their own game.
I think the charger size is way more limited by the cost efficiency and reliability than our current technology itself, but I stand corrected if there's really something new here.
Good luck guys, my order is set.