First off, I'd like to thank you guys for all this great information in the forums. I've been here for awhile, but I haven't posted pretty much at all because I have been able to find pretty much whatever I wanted to know buy searching. I've learned a lot, so thank you for that!
I've never seen a direct answer to this though: how much ripple would you say is acceptable for the 9mm NDB7875 at around 1.8-2.0 amps? From what I understand, you can strobe lower powered diodes without really worrying about it but the high current diodes are more vulnerable to power fluctuations.
I am designing a switching driver to convert 12V from an ATX power supply down to about 8.5V or so with an LM2596 switching buck regulator. (datasheet: http://www.ti.com/lit/ds/symlink/lm2596.pdf) Then I'm thinking of going with an LT1085 linear regulator (datasheet: http://cds.linear.com/docs/en/datasheet/108345fg.pdf) to smooth out the ripple a bit (it has better ripple rejection than other linear regs, although it's probably only like 25dB at 150 kHz) and set it up for constant current without the intense heating from the raw 12V.
If the ripple isn't such a huge deal, or I have better ways of dealing with it than a huge inductor, I might just not use the LT1085 at all.
I also want 100% duty cycle out of the thing, so I am considering rigging up a watercooling setup. 12V pumps are pretty cheap on ebay, and I believe I can set it up fairly easily without spending a lot. Is watercooling overkill? I figure that's probably the reason it's hardly mentioned in these forums lol.
Regardless, I'll be sure to post pics of the whole setup when I am finished- but I still need to work these things out and order a few parts first! :beer:
I've never seen a direct answer to this though: how much ripple would you say is acceptable for the 9mm NDB7875 at around 1.8-2.0 amps? From what I understand, you can strobe lower powered diodes without really worrying about it but the high current diodes are more vulnerable to power fluctuations.
I am designing a switching driver to convert 12V from an ATX power supply down to about 8.5V or so with an LM2596 switching buck regulator. (datasheet: http://www.ti.com/lit/ds/symlink/lm2596.pdf) Then I'm thinking of going with an LT1085 linear regulator (datasheet: http://cds.linear.com/docs/en/datasheet/108345fg.pdf) to smooth out the ripple a bit (it has better ripple rejection than other linear regs, although it's probably only like 25dB at 150 kHz) and set it up for constant current without the intense heating from the raw 12V.
If the ripple isn't such a huge deal, or I have better ways of dealing with it than a huge inductor, I might just not use the LT1085 at all.
I also want 100% duty cycle out of the thing, so I am considering rigging up a watercooling setup. 12V pumps are pretty cheap on ebay, and I believe I can set it up fairly easily without spending a lot. Is watercooling overkill? I figure that's probably the reason it's hardly mentioned in these forums lol.
Regardless, I'll be sure to post pics of the whole setup when I am finished- but I still need to work these things out and order a few parts first! :beer:
