As the name suggests, DOB is to put the constant current driving source Driver of the LED on the aluminum substrate.
Let's take a look at some of the misunderstandings about DOB:
1. Misunderstanding 1: DOB is called de-powered, it seems that with DOB, no power is needed. In fact, it is impossible for any LED lamp to light up without power supply, so it is absolutely impossible to go to the power supply. Only after putting the power supply on the aluminum substrate, it looks like the external power supply with the shell has been removed, but the power supply is definitely not removed, but the power supply is placed on the aluminum substrate.
2. Misunderstanding 2: Treating DOB as a brand new power supply, thinking that without this power supply, it is impossible to produce light engines. In fact, all LED constant current drives can be summarized into two types, one is a switching power supply, and the other is a linear power supply. In principle, both power supplies can be placed on the aluminum substrate, but the number of components of the switching power supply is large, and it will take up a large area to put it on.
3. Misunderstanding 3: I think there are many different types of DOB power ICs on the market. There are indeed many manufacturers of such linear DOB power ICs, but their principles are all the same. They are all based on the first segmented dimming technology IC produced by ExClara in Silicon Valley, USA. The so-called segmented dimming means that when the rectified half of the sine wave voltage rises to a certain value, the first string of LEDs are turned on, and when the voltage further rises to a higher value, the second string of LEDs are turned on,... And so on.
4. Misunderstanding 4: I think that as long as the number of segments is increased, the efficiency of the system can be improved (some people say that it can be increased to 90%). The only advantage of increasing the number of segments is that the current waveform is as close as possible to a half sine wave, so that the power factor can be as close to 1 as possible. But it has no effect on the efficiency of the system, because it does not change the nature of the most basic linear power supply, so the efficiency is still 85% at 220V.
