Summary this time as a lighting drive power efficiency trick:
1.主电流回路PCB尽量短。
The 1 main current loop PCB as short as possible.
LAYPCB的经验,及布局,这个没什么,快速的方法就是多看大厂的作品。
The experience of LAYPCB, and layout, this not what, fast way is to look at the Dachang works.
2.优化变压器参数设计,减少振铃带来的涡流损耗。
2 transformer parameters optimization design, reduce the eddy current loss caused by ringing.
这个比较难,先要把电磁基础知识掌握,设计合理的变压器,最要紧的是耐心,哪怕是想到能提高0.5%的效率,也要去尝试。
This is more difficult, to master basic knowledge of electromagnetic transformer, design reasonable, the most important thing is patience, even if it is expected to improve the efficiency of 0.5%, also want to try.
3.合理选用开关器件。
3 reasonable choice of switching devices.
这个就是成本和性能的平衡了,什么样的客户要求,用什么样的器件,但得合理。如果要效率,毫无疑问COOL MOS ,低VF输出二极管
This is the cost and performance of the balance, what kind of customer requirements, what kind of devices, but a reasonable. If you want to efficiency, there is no doubt that COOL MOS, low VF output diode
4.输入EMI部分优化设计
The 4 input part EMI optimization design
如果过安规,这部分考究得比较多,主要就是经验了。
If the safety regulations, this part of research more, mainly is the experience.
5.选择高效率的拓补结构
5 select efficient topological structure
这个是方案选型的开始,例如PWM和QR PFM,当前提客户提出效率要求,就要评估选什么样的拓补
This is the beginning of project selection, such as PWM and QR PFM, the current customers put forward efficiency requirements, to evaluate the topological what
6.选择好的电解电容
6 select the electrolytic capacitor
很多人忽略了这个,电解的损耗很大,陈永真老师有个文章中就有详细的解说
Many people ignore this, electrolytic loss is very large, Mr Chen Yongzhen has an article will have a detailed explanation
7.启动部分功耗设计
7 start the part of power design
有效率的前提下,就要考虑,目前很多芯片都有HV启动脚,启动电流也越做越低,这点就是要对新型器件多了解,当然了,还有外加电路无损启动等,我认为不适合LED驱动。
Under the premise of efficiency, should consider, at present a lot of chip has HV feet, starting current is also growing in low, this is to learn more about the new device, of course, there are additional circuit nondestructive start, I think it is not suitable for LED driver.
8.芯片辅助供电优化
8 chip auxiliary power supply optimization
这点ST的L6562D应用文档中有指出,15V为最佳,但LED一般又为宽电压输出,所以我的选择是加一级线性稳压,使芯片工作在15V来降低损耗。
This ST L6562D application documents are pointed out, 15V is the best, but LED generally and for wide voltage output, so my choice is to add a linear regulator, the chip work in 15V to reduce the loss. |