High Voltage, low power flyback design
Hi,
I want to use the stackfet method for a new design with particular specifications. I can have very high 3 phase input voltage, but the current is always constant at about 3mA, which gives low power available. I need at the output multiple voltages (2.5V, -2.5V, 1.8V, 1.0V) at low power that could be generated using switchers from a lower voltage, like 12V or 5V. I was looking at power harvest, but wanted to give a shot at higher voltage solutions to take advantage of the power available.I am open to any suggestions.
What device do you suggest? Are your devices suitable for that kind of requirements? Can I design something in PI expert?
Best Regards,
Yan
Comments
OK, the 5V will only be used to supply the other switchers for the post regulations, so the tight regulation is not needed i think. What is low enough for the power output of the flyback? It will be more in the 300-500mW range since I don't have a lot of power at the input either. Is there a minimum for the LNK switches? I will make sur the output is not loaded in the first place to ensure the 5V output succeeds with its ramp up.
And i just find that there are some documents in PI website possibly match your requirement. PLS check DER058 or DI124.
http://www.powerint.com/sites/default/files/PDFFiles/der58.pdf
http://www.powerint.com/sites/default/files/PDFFiles/di124.pdf
Based on your explaination, two stage solutions will be used for your application. The first stage is a flyback to convert from high AC input to 12V or 5V, and post regulators will be used for lower voltage output.
My suggestion is using TNY switch for the first stage if you want tight regulation on 5V/12V, or using LNK switch if the 12v/5v regulation is not a problem and the power output of flyback is low enough.
Once you decided whci family to be used, you can design the flyabck using PI expert.