Hiperlcs issue

Posted by: erdemdurul on 08/12/2015

Hi all;

I have a special project that is street lighting. I have designed circuits as RDR292

It's working well but I want to make constant current led driver with dimming function (especially pwm dimming).İt's a constant voltage design in RDR292

Can I change my driver on output stage like decribe in RDR382 ? I think, both design is using same hiper lcs. if not ,do you

have any design for this,

Also How can I design HiperLCS with pwm dimming?

my design requirement are listed below,

input voltage= 220-240V

PF>0.95

efficiancy>%90

power = 100W - 150W

output voltage = max 47V constant current especially 2.1A

best regards

Comments

RDR382 is preferred due to the core and bobbin availability.
Also, it has the CC circuitry. However it accepts a 0-10V analog signal, and you need to add a little bit of circuitry to convert your PWM signal to 0-10V.

Hi Tucker,

I don't want to change pfs stage in my circuit.because I return the back. I'll have to draw new pcb. so can I replace output stage of RDR292 CV to CC

Yes you can.

Hi Tucker,

I have replaced circuit from CV to CC. İt's working. But Voltage range is very narrow that it's changing voltage range 2-3Volt depend on led. do you have

any idea or comment this situation. how can I obtain wide voltage range? also What is the Vccs voltage value? I applied 8V on it.

Many thanks for all,

if you are running at CC, and your output voltage is expected to be limited range determinded by the LED. is it the question? VCCS neds to be 12V norminal. 8V is too low.