Can I Design an All-in-One AC to DC LED Driver with PWM Dimming?

[aiq25]

Hello. I'm trying to design a AC to DC LED driver with PWM dimming. I have a design that I can use with the LM3406HV but I would like to design something that I can wire up 110V AC mains line. With the LM3406HV I need a DC power supply. I was thinking about using a switching power supply but if I can make one that's all-in-one then it will be better. I need 8 drivers with 42V DC at 850mA output. I'm planning on using the PWM for dimming. I don't think I need all the power that I'm planning on having but it's nice to have the power just in case I need it.

If anyone is wondering, I'm trying to build a LED lighting system for a reef aquarium. I know there is a lot of tutorials out there for this already but I thought I would ask here and see what the opinions are. Also, I could buy a lighting system but I like building system, so that's why I would to design something and build it myself.

 

[rbelli1]

I would highly suggest using something like the following:
http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_301306_-1

This can be adjusted to 55V and would be great to supply power to as many LM3406HV as you need. They also make other sizes. Using an off the shelf off line supply eliminates certain dangers that are inherent with working with high voltage mains power.

If you do decide to go directly to the power line yourself you will want to be galvanically isolated and keep the high voltage away from the water. For the power rating you are looking at it is likely you will need to wind the transformer/coupled inductor yourself. Find a manufacturer of offline switching controllers that have a magnetics design tool you can use. I know Power Integrations has one. The other (TI, National, Linear, ADI, etc.) players in that field likely have something to help with magnetics design as well.

BoB