OK, so I have an LED driver (already built into a circuit) with the mc34063 chip on it.
For reference, its set to output 750mA using a resistor to sense the feedback current, with 12V input.
What I wanted to know is, has any one used this chip before, and is it possible to dim the LED using PWM? What I was thinking was that I PWM the feedback pin. I know this works on other constant current chips but they actually say in the data sheet that you can do it. Should this be possible? Or would you just end up putting too much current into the feedback pin and over driving the LED?
The other chip I have used PT4115 is made so that you can set the upper limit for current with a resistor, and use PWM to vary the current from 0 to 100%. COuld you do the same thing with the mc34063?? OR is there another way you could dim the LED?
Thanks..
For reference, its set to output 750mA using a resistor to sense the feedback current, with 12V input.
What I wanted to know is, has any one used this chip before, and is it possible to dim the LED using PWM? What I was thinking was that I PWM the feedback pin. I know this works on other constant current chips but they actually say in the data sheet that you can do it. Should this be possible? Or would you just end up putting too much current into the feedback pin and over driving the LED?
The other chip I have used PT4115 is made so that you can set the upper limit for current with a resistor, and use PWM to vary the current from 0 to 100%. COuld you do the same thing with the mc34063?? OR is there another way you could dim the LED?
Thanks..