I'm working on a project to make an adjustable power supply controlled by an arduino. Since the arduino doesn't have a DAC built in, I'm using a two stage RC filter to convert the PWM to DC to control the output voltage and a second PWM with a comparator to limit the current.
My overall design goal is to have a 20-40W supply capable of going up to 20V. I'm going to end up characterizing boost regulators with it and will need to supply 2.2V @ 9A. What scares me though is to be able to have 20V output I'll need Vin to be maybe 24V, so I know the LT3083s will be dissipating quite a bit of heat.
How efficient is the LT3083? I've looked at the datasheet and they do have a high efficiency, high current circuit but the output voltage is only 10-12V. Is there a buck converter that has a voltage set pin rather than just using a voltage divider to the feedback pin? Or would I have to use a digital pot to control the output voltage?
My overall design goal is to have a 20-40W supply capable of going up to 20V. I'm going to end up characterizing boost regulators with it and will need to supply 2.2V @ 9A. What scares me though is to be able to have 20V output I'll need Vin to be maybe 24V, so I know the LT3083s will be dissipating quite a bit of heat.
How efficient is the LT3083? I've looked at the datasheet and they do have a high efficiency, high current circuit but the output voltage is only 10-12V. Is there a buck converter that has a voltage set pin rather than just using a voltage divider to the feedback pin? Or would I have to use a digital pot to control the output voltage?
Attachments
-
48.7 KB Views: 25