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Main => Builders Discussions => Topic started by: 727737Nut on April 13, 2015, 07:19:39 PM

Title: Looking for a dimmer
Post by: 727737Nut on April 13, 2015, 07:19:39 PM
Trying to find a 0-5V light dimmer that is high side pwm dimmer.  Everything im finding is low side ie PWM the ground side.

Thanks
Rob
Title: Re: Looking for a dimmer
Post by: Jan737 on April 14, 2015, 05:27:05 AM
Just curious, why a high side pwm dimmer?

This is a DYI solution, or are you looking for a ready one?

http://project.irone.org/power-width-modulator-with-555.html (http://project.irone.org/power-width-modulator-with-555.html)

Jan
Title: Re: Looking for a dimmer
Post by: 727737Nut on April 14, 2015, 06:20:08 AM
All Real aircraft panels get the ground through the frame of the aircraft.  They also run on 5VAC so it is not a big deal. Butwhen you drive them with 5Vdc like we do then it becomes a big deal.  They are not isolated like LED lighting is.  Hence the reason for high side dimmer. 
Thanks for the link but that is a low side dimmer. 
Rob
Title: Re: Looking for a dimmer
Post by: KyleH on April 14, 2015, 07:55:40 AM
If you want to make it high side, change the MOSFET in the circuit to a P-channel, and swap the location with the motor.

Ones that can deliver the kind of power you are looking for are pricy. That's why most everything it low side drive.
Title: Re: Looking for a dimmer
Post by: 727737Nut on April 14, 2015, 09:01:58 AM
DUH! moment, Think back Rob! 60's 70's cars  lol  simple and works!

http://www.aircraftspruce.com/catalog/elpages/rheostat.php (http://www.aircraftspruce.com/catalog/elpages/rheostat.php)
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