EEVblog Electronics Community Forum
Electronics => Projects, Designs, and Technical Stuff => Topic started by: lja246 on November 09, 2022, 06:54:15 am
-
Hi all,
I was looking for some advice for a boost converter. The specs that I need are the following:
Vin = 11/28V (12v and 24v cars and trucks)
Vout = 32V
Iout = 1.5A
What type of boost converter IC would you recommend for this type of specs?
I have looked at some but I can't find any that specifically say in the datasheet that they can boost from 11v to 32v at 1.5A.
-
Look for a boost switching regulator controller that uses an external power transistor. The peak switching current needs to be like 4.5 amps to make a 32 volt output from 11 volts. Analog Devices has a bunch.
The LT1070 almost meets your requirements although it uses an internal power switch.
-
1.5A means you should be able to find a monolithic block IC that includes everything you need except for the inductor and input/output caps. ( eg built in mosfets, synchronous rectification etc..) It keeps things simple and quick to get working.
Downside is cost is usually little higher than a simpler IC that needs external fets/diodes etc
The hard bit is finding your chip is now out of stock 1 week after you got the prototype working
-
UC3843 will certainly do, or LM3481 a more modern example. These are external switch, so need more component selection and layout work.
There's probably a SimpleSwitcher (and other brand equivalents) say in D2PAK or TO-220-5 or whatever, rated for about that. Maybe just barely, I'm not sure. These are integrated regulators with the switch and loop compensation all done, just add inductor, diode (usually), capacitors and a very modest layout.
Follow the layout in the application section. It will be a good start at least, if not ideal, as appnotes often fall short of. Pay particular attention to short and wide ground paths, use wide pours / ground plane, and stitching vias where planes are intersected by traces.
As mentioned above, uModule and such devices can get you there even faster, but at greater expense. Mind, some of them are still quite noisy, or require good bypassing and layout anyway (namely, those with inadequate onboard bypassing). At least, that was my experience with LTM4607 a long time ago; hopefully they've improved since then, but in any case, pay attention to the internal circuit, and the age and cost of the design (LT is famous for supporting legacy parts, they will show up in your searches -- at legacy prices too!).
There's also generic DC-DC modules, which range from eBay shovelware specials, to major brand names (Murata, CUI, etc.) with proper spec sheets. These very visibly (when not potted) use off the shelf controllers/regulators and everything, they're just the convenience of a ready-to-go module (and with pins instead of SMTs if you need that). They may still specify external filtering, but shouldn't be as strict on layout, at least until you need to meet EMC levels. (Like, a careless layout might be, say, 10 or 20dB above limits -- not great, but not ludicrously blown up. Good enough you might not notice it in the lab, at least until you do some small signal probing.)
Tim
-
I think you can take a look at XL6009
http://beriled.biz/data/files/XL6009.pdf (http://beriled.biz/data/files/XL6009.pdf)
Its maximum output current is 5A.