1. The main current loop PCB is as short as possible. LAYPCB's experience and layout, this is nothing, the quick way is to look at the works of big factories.
2. Optimize transformer parameter design and reduce eddy current loss caused by ringing. This is relatively difficult. First of all, we must master the basic knowledge of electromagnetics and design a reasonable transformer. The most important thing is patience. Even if we think of improving the efficiency by 0.5%, we must try it.
3. Reasonable selection of switching devices. This is the balance of cost and performance, what kind of customer requirements, what kind of device, but it must be reasonable. For efficiency, there is no doubt COOL MOS, low VF output diode.
4. If the optimized design of the input EMI part exceeds the safety regulations, this part is more researched, mainly because of experience.
5. Choosing a high-efficiency topology structure This is the beginning of solution selection, such as PWM and QR PFM. At present, when customers request efficiency requirements, it is necessary to evaluate what topology to choose.
6. Many people choose a good electrolytic capacitor. Many people ignore this. The loss of electrolysis is very large. Teacher Chen Yongzhen has a detailed explanation in an article.
7. Under the premise that the power consumption design of the startup part is efficient, we must consider that many chips have HV startup pins and the startup current is getting lower and lower. This is to understand more about new devices. Of course, there are additional circuits. Non-destructive startup, etc., are not suitable for LED driving.
8. The optimization of the auxiliary power supply of the chip is pointed out in ST's L6562D application document that 15V is the best, but LEDs generally have a wide voltage output, so my choice is to add a level of linear voltage regulation to make the chip work at 15V to reduce loss.