Looking for suggestions on the schematics that I came up with. Everything was based on the datasheet (almost).
I am anticipating each LM338 to produce [(35V-32V)*8A]/2 = 24W/2 = 12W of heat.
I found this heatsink here by Ohmite - https://www.mouser.com/ProductDetail/588-FA-T220-64E - hopefully this will be enough if I mount each regulator on its own heatsink.
I am also wondering what that 1uF el capacitor at the input is doing? Can I replace that with bigger capacitance one (10uF or 47uF)?
Here is what datasheet suggests:
Any suggestions and help are appreciated!!
I am anticipating each LM338 to produce [(35V-32V)*8A]/2 = 24W/2 = 12W of heat.
I found this heatsink here by Ohmite - https://www.mouser.com/ProductDetail/588-FA-T220-64E - hopefully this will be enough if I mount each regulator on its own heatsink.
I am also wondering what that 1uF el capacitor at the input is doing? Can I replace that with bigger capacitance one (10uF or 47uF)?
Here is what datasheet suggests:
Any suggestions and help are appreciated!!
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If you actually want 10A output, I'd use the 15A circuit in the data sheet, fig. 30.
This will spread out the heat over three devices and sinks, instead of just two.
But you are at the limit of the output voltage possible.
And the heat sink is likely inadequate, considering AC line voltage variation, etc.
Is this for a lab supply, or an amplifier?
This will spread out the heat over three devices and sinks, instead of just two.
But you are at the limit of the output voltage possible.
And the heat sink is likely inadequate, considering AC line voltage variation, etc.
Is this for a lab supply, or an amplifier?
I intend to use this with two channels of 2xLM3886 in parallel. Looks like each channel will draw 7A max or 14A total. Having two LM338 times two rails should give me 20A max out.
Should then each LM338 conduct 14A / 4 = 3.5A max?
With Pdis = 3.5A * 3V = 10.5W?
I'd use one power supply per channel for sure. Maybe you can get away with a single power transformer.
I have 400VA 2x25V transformer by Antek - AS-4225 https://www.antekinc.com/as-4225-400va-25v-transformer/
Hopefully that will work. I might need to drop output voltage after regulators to 30V...
Yes, but you have to be sure the regulator will not drop out under worst case conditions.
Low AC line, transformer drop at full load, ripple voltage on first capacitor under high current, etc.
Low AC line, transformer drop at full load, ripple voltage on first capacitor under high current, etc.