Why a Factory Supply USB Power Delivery 20W Wall Charger is the Best Fast Charger

Why a Factory Supply USB Power Delivery 20W Wall Charger is the Best Fast Charger

Unless you’re still rocking a Palm Pilot from the ’90s, most of us use smartphones that recharge via USB. But most phone chargers are junk, from the chintzy Apple ones that come with your iPhone to the random assortment at your local drugstore.

Thanks to major growth in integrated circuitry, charge controllers, adapters, and cords, we could soon see a world of fast charging, where phones can go from 0 to 100% in minutes rather than hours. But first, we need to get rid of the old-school chargers that bog down the process.

That’s why the best chargers aren’t just faster but more efficient as well. They’re also more compact, so you can fit them in your bag and keep them in your desk drawer at work for a quick boost during lunch. The best chargers are also designed with better-quality components, which can reduce noise and vibration, as well as improve safety by reducing the risk of overheating or short-circuiting.

The best chargers for your smartphone or tablet can cost as little as a few dollars, but they’re not necessarily the same thing. Many of the cheap chargers we’ve tested have a reputation for poor quality, and some are even dangerous to use (check out our article on how to spot counterfeit USB-C chargers). This Monoprice charger is one of the most inexpensive that we’ve tested so far, but it has extremely poor regulation, as shown by the wide yellow line in this graph. The voltage is fairly constant at low loads, but starts dropping rapidly as the load increases, and then maintains a high current (which causes the steep downward slope in the line). The peak-to-peak distortion on this chart is pretty bad as well, with a lot of tall spikes on the frequency spectrum and lots of narrow harmonics at the 28kHz switching frequency.

The real deal is a proper USB Power Delivery adapter, which has the physical USB-C connection (the oval-shaped, reversible plug found on most newer smartphones) and the USB 3.1/3.2 or higher specification that can boost the voltage from 5V to up to 20V at up to 3Amps. Some fast-charging standards like Qualcomm’s Quick Charge or Samsung’s Adaptive Fast Charging exceed the USB-PD spec on purpose, but they’re backward compatible and have built-in safety features to prevent overheating and other issues. We’ve tested several different USB-C chargers for smartphones and tablets, including the Nekteck 60W Type-C Wall Charger and the Scosche PowerVolt Fast Charger, both of which support a variety of cables. The latter also includes a USB-C-to-Micro-USB cable, which can be used to recharge non-fast-charging devices such as headphones and e-readers.