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LED dimmers for 5w/12watt white lamps

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vimalkhanna

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Need to have 10% to 95% dimming facility for my 5watt LED white light LED .
Pulse control ,,phase control ,pulse suppression control circuits are needed with RFI filtering .
Suggestions ??
 

Designed Pulse position modulation rather than PWM .
The frequency was lowered and the Vmax. was also trim controlled thru a TL431.
The solution was reached .
Detailed readings of load currents were monitored and extra design steps were taken to improve cutin voltage switching .
However the LEDs start with a jerk.
 

Designed Pulse position modulation rather than PWM
Click to expand...

PPM does not change the space/mark ratio and it's used in different applications ..
Start with 555 in its classic 2-diode PWM configuration .. see attached picture ..
Then you can add an RF-choke and some caps to reduce interference, if required ..

IanP
:wink:
 

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  • PWM_555_N-ch.png
    PWM_555_N-ch.png
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there are no attachments in file ..like to see your detailed schematics pic..
 

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