1. SMD
There are many kinds of low-power surface mount packages. Their advantage is that they are small in size and low in power. For example, the common model number is 2835, which refers to the size on its side. Generally it is a rectangle, 2835 is 2.8mm×3.5mm.
2. COB
COB is an integrated package, which seals a number of small chips on a substrate, and uniformly coats phosphors on it. It is about the size of a coin, and of course there are bigger ones, and some are as big as half a book. Its advantage is that it can gather a lot of light-emitting points together to make a spotlight lamp, or a lamp with a little higher power.
The common model is basically based on the diameter of its circle, and of course there are also square packages. The models of each manufacturer are different, but they are actually a combination of chip + phosphor, but the combination is different.
Whether it is SMD or COB, each has its own purpose. You can't say who is good and who is bad. The difference between them is that the SMD is scattered and you can use it flexibly, while COB is integrated for you, and it is well thought out. The method and method of application, you just choose it.
