Why can't PI Expert 7.1 design constant current led driver?
Hello,
I want to make a constant current led driver whit TOP-GX(Top249Y). There is a "Led Driver" box when I start to design smps via PIE 7.1 . But there is no changes between whit CV smps. Will you develop and add this spesification into PIE 7,1 or What must do for cunstant current led driver whit TOPGX(249Y)...
And I want to drive leds in large voltage space. For example I must drive 3 leds or 10 leds whit same supply.So it will be like that..
Vout: 3V-24V
Iout: 700mA
Thanks...
Best regards,
Mahmut
Comments
sure, I must make a constant current supply. But I have flexible output voltage and constant current...
Thare are many reference designs about constant voltage and constant current. But I need just constant current, not CV.
What is the power level you require? It is possible to use a LinkSwitch-II device to design a LED driver with ease.
In anycase you will need some sort of overvoltage protection to protect against the event that one LED in the string fails open circuit. The constant voltage can provide the OVP protection. (JUst set the CV voltage to be a tad higher than the combined forward voltage of the LED strings)
I think LinkSwitch-II is not capable for me. So I generally use little high power(10W-30W) And I guess TOP GX is more suitable for me. Now what must I do for drive leds as flexible counts.
You are right. Linkswitch-II cannot deliver so much power.
I would recommend that you take a look at the following links
http://www.powerint.com/sites/default/files/PDFFiles/der136.pdf
This is a high line only 75 W driver (CC only)
http://www.powerint.com/sites/default/files/PDFFiles/der168.pdf
This is a single stage 20 W driver with PFC
to be honest you wouldnt want it to do you a led driver.....just do a constant currrent supply.
also there are so many different leds............it couldnt know which ones you were using.