Master chip

Yuxin yx6623 has built-in high-precision comparator fixed off-time control circuit, three-function control circuit, etc. It is suitable for single or multiple high-power LEDs to be used in series and parallel.

characteristic

•  Wide input voltage range: 2.5v~24v
•  High efficiency: up to 90%
•  Three functional outputs: 100% bright-25% bright-flash (5Hz)
•  Internal integrated voltage regulator: 3.6v
•  Maximum operating frequency: 1MHz
•  Chip power supply undervoltage protection: 2.5v
•  Peak current sampling voltage: 250mv
•  Adjustable off time

I personally think that the parameters of this chip are very good, but it is not easy to buy. I bought it on Taobao, 9.9 for 10 pieces, and the average price is about 1 yuan.

Component selection

Schematic diagram

Official schematic diagram and component selection formula

Just use Rcs formula and calculate it

The inductor I used is a 100uH 5026 inductor.

c1 does not need to be welded

Then let’s talk about the switch. The function selection of yx6623 is realized by turning off and on the input power of the switch. I used a normally closed switch and a rocker switch to control the switch and function switching.

pcb