funkyfish77
New member
OK my goal with this is a simple affective pwm DC/DC driver for one 20 watt multichip LED . I started here http://pcbheaven.com/circuitpages/LED_PWM_Dimmer/
Well this is what I have now it works fine.
I don't have a extra led yet so I have not tested it qon a 20 watt led yet . Changes I have made to the circuit are r1 got changed to 1kohm the pot is 20k and I changed the transistor to a tip42. Here is the schamatic
Question 1 from what you can see is there anything I can do to my curcuit to make it better or more dependable without adding much complexity?
Question 2 when I check my voltage on the output it vary's in voltage depending on the brightness of the leds . I thought a pwm signal would still read 12v no matter the brightness
Of the leds?
Well I'm open to all opinions so lets have them.
Thanks in advance
Funky
Well this is what I have now it works fine.
I don't have a extra led yet so I have not tested it qon a 20 watt led yet . Changes I have made to the circuit are r1 got changed to 1kohm the pot is 20k and I changed the transistor to a tip42. Here is the schamatic
Question 1 from what you can see is there anything I can do to my curcuit to make it better or more dependable without adding much complexity?
Question 2 when I check my voltage on the output it vary's in voltage depending on the brightness of the leds . I thought a pwm signal would still read 12v no matter the brightness
Of the leds?
Well I'm open to all opinions so lets have them.
Thanks in advance
Funky
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