Omit the filament windings -- LTM8033 from Linear

[jackinnj]

I saw this in a recent email from Linear Tech -- the LMT8033 is a buck converter module 3.6 to 36Vin, 0.8 to 24V out @3.6A-- very low radiated noise. Adjustable per usual:

http://cds.linear.com/docs/Datasheet/8033f.pdf

[firechief]

ah yes- complete with a table outlining componet values for various voltages. The are really making it easy. Thanks Jackinni - many uses I say.

[tomchr]

Yeah..... Good luck soldering that one.

~Tom

[Bas Horneman]

Yeah..... Good luck soldering that one.

Nothing a simple groupbuy could not fix. . Presoldered to some pcb...et voila.

Forgive me though for asking this. But what are the advantages of such a thing? Can it output ac in high freqs?

Or is it more suitable for the preamps in vogue now where you can plug and play dht's with all kinds of filament voltages?

[kenpeter]

http://focus.ti.com/lit/ds/symlink/tps5450.pdf

[firechief]

Originally Posted by tomchr

Yeah..... Good luck soldering that one.

~Tom

Yea I know what your mean. And you have a good point. However I could do it. Hot air is the trick.
I think that Jackinni's idea for a fix when filament windings are not avaiable, or not able to produce enough current is the obvious first idea. Anywhere that you need a higher voltage DC from a lower one. I wonder if you could put two back to back and get + and - for a solid state amp? If someone wants to lay out a board and have it built, I will install the parts properly no cost to anyone on the forum. Send me 10 I'll knock it then in one sitting.

[jackinnj]

Yes, if you take a look at some of SY's designs using the LM317 as a filament regulator, then lifting the filament well above ground for a cathode follower, use this module instead. The switching frequency is in the 100's of kHz.

Bas, if you think it's appropriate for a GB, any number of folks could have them burned and assembled at 6.3VDC, 12.6VDC etc for mounting on a couple of molex 0.100" headers.

[firechief]

Originally Posted by kenpeter

http://focus.ti.com/lit/ds/symlink/tps5450.pdf

Ken Thats a cool part too. Needs and inductor, but thats not too hard. The first part needs only 2 resistors and 3 caps. I hope this is not a solution looking for a problem in DIY.

[tomchr]

Originally Posted by firechief

Yea I know what your mean. And you have a good point. However I could do it. Hot air is the trick.

I've soldered SMDs with exposed DAP and such with a heatgun. It works alright. I also have access to a METCAL hot air reflow station at work. I *can* do the work. But why? The LMZ-series of SimpleSwitchers from National are way easier to work with. A couple of passives and you're set. Check out the LMZ12003 for example. Or LMZ14203. Easy to solder too. What's not to like?

~Tom

[firechief]

Yep - Those packages are pretty user friendly. 3 resistors and 4 caps. Like 8 parts plus a board and some headers. I wonder how much intrest there realy is?