USB Wall Chargers For Better Convenience
Today, built-in USB chargers are becoming more and more popular, even popping up in coffee shops and restaurant chains. New homes are now built with USB wall chargers, while existing home renovations now include replacing old AC receptacles with USB chargers.
Clearly, charging without an adapter provides the convenience of fast charging and also reduces clutter. Given the increasing adoption of USB wall chargers, the most unusual challenge is how to meet stringent thermal performance requirements to meet safety codes. You can also find affordable wall chargers by visiting this website.
Unlike portable or external AC / DC adapter designs, a built-in USB wall charger can only dissipate heat through the safety cover of the outlet. The one or two-element boxes behind the cover are surrounded by thermal insulation material.
The front cover cannot exceed 60oC. Typically 4 "(L) x2.75" (W) x2.5 "(D) dimension, actual space to house AC / DC power solution is much smaller than indicated by the Dimension data The reason is the wiring layout through the back and connection to receptacles on the front of a distribution box.
The maximum allowable amount of power dissipation behind the plug cover is 2-3W. For two 10W USB ports, you need 90% efficiency to control the loss to less than 2W.
With emerging applications such as the USB Type-C and USB-PD connector, consumers will be looking for charging powers above 20W, which can charge devices such as smartphones, tablets, and ultrabook computers.
A high-efficiency, high-power-density AC / DC solution is a must for a USB wall charger. Many companies are working on a high-density, high-efficiency solution to meet this challenge.