DIYEFI.org Forum

Here's the reference design from the datasheet: http://koti.mbnet.fi/~vendigo/stuff/LM3694-referencedesign.jpg It looks pretty neat, the only problem is it's designed for 4-layer PCB and the bottom layer is supposed to be untouched ground plane. However, I think we're going to need only one LDO outp...

The software to create the 3DS was Rhino3d, which I imported to LW and then sent to Wings as LW Object. I had to do the intermediate LW step because for some reason Wings wanted to rotate every part around it's own axis instead of common or origin and that messed up the pins pretty good. There must ...

http://koti.mbnet.fi/~vendigo/stuff/3D-footprint2.png Well what do you know, friends in low places to the rescue! As it's impossible to export a multi-body part as STL, I had to have the STEP converted into 3DS first (by a former colleague) and then into VRML. He also got the polygon model optimize...

http://koti.mbnet.fi/~vendigo/stuff/3D-footprint.png I actually modified the geometry to match the PCB and not through the mesh modifier panel on the footprint editor. I was thinking about doing the pins for the panel though, so it'll mean redoing the whole deed. I REALLY wish the developers had ch...

Excellent! I'll check it out in the morning. Greatly appreciated!

I'm building the circuit in LTSpice, I have the LTpowerCAD too but the damn thing won't work properly! Anyway, I'm working on it. I'll try some filter systems and we'll see how it turns out. Too bad the switching systems are finicky about their layout so you can't just build one on a breadboard or e...

I think I found a pretty good candidate. The LT3694 from Linear Technologies has adjustable output voltage and switching frequency (from 250kHz to 2.5 MHz), 2.6A Iout, input range of 4-36V and even two LDO regulator controllers (requires external NPN BJT's). It also has soft start, so it should beha...

I did some searching on the subject and came up with two articles and they were quite toward using switched power supply with ADC's. http://www.analog.com/static/imported-files/tech_articles/Powering_High_Speed_ADCs.pdf http://www.analog.com/static/imported-files/rarely_asked_questions/RAQ_tamingADC...

I was looking through the schematics, the analog inputs already have a low pass filtering with 1.6kHz cutoff frequency... shouldn't that pretty much cut all the SMPS-generated noise unless the entire board oscillates at some sub-harmonics below it?

The design point load is 2.5A, it's an assumption on worst case scenario (everything installed and working at full load). The voltage ripple is probably much less with lighter load.