I'm looking for an integrated component or basic circuit with high efficiency DC-DC regulator that will allow me to output 19.5v at 3.3 (or more) amps from a 24v battery. I could step up from 12v but I assume I'm going to get more efficiency with 24-> 19.5.
What should I be looking at? I'm a fan of the Tracopower range of converters: https://www.tracopower.com/products...converters/non-isolated-step-down-regulators/
I assume I'm not going to get away with a neat drop-in gadget like that, particularly at 3A+ output.
Any pointers would be appreciated....
Oh, I'm basically wanting to power my laptop (PSU is 19.5v 3.3a) for extended periods (4 hours) more efficiently than with an inverter based solution.
Thanks!

 

hi wed,
Welcome to AAC.
Look thru this link, lots of options.
E
https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=buck+converter+24v&_sacat=0

 

hi wed,
Welcome to AAC.
Look thru this link, lots of options.
E
https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=buck+converter+24v&_sacat=0

Thanks for the prompt response Eric! I was under the impression that a buck converter was not very efficient, but I'm a noob. *EDIT* seems I'm very much mistaken - I'm getting reports of 90% efficiency from Google
Am looking at using one of these goodies as the source:


https://www.omniflex.com/dsview.php?hid=C2197B
Anyone know of a similar product that possibly outputs variable voltage?

 

Just adding to the thread - I found this:
https://www.emea.lambda.tdk.com/za/products/product-details.aspx?scid=394

98% efficiency reported with variable output. Fantastic!

 

hi w,
They look a good quality unit, no idea of the cost.?
The eBay modules are inexpensive, depends on your budget.

E
Are you in RSA.?

 

hi w,
They look a good quality unit, no idea of the cost.?
The eBay modules are inexpensive, depends on your budget.

E
Are you in RSA.?

Quality is good, but yeah, price is a bit on the upper end... mouser is around $75 to me and RS locally I can get them for $40 which isn't the worst. Those buck converters look pretty decent and I can source locally.

*EDIT* found this:
https://www.diyelectronics.co.za/st...-converter-buck-in-45-32v-out-08-30v-12a.html

I am indeed from RSA

 

hi w,
That should get the job done.
Only 160Rand [ £18 GBP]
Lets know how it goes.
E
OT: We have a small farm in PE.

 

hi w,
That should get the job done.
Only 160Rand [ £18 GBP]
Lets know how it goes.
E
OT: We have a small farm in PE.

Ah Fantastic! At least you understand why I'm buying this gadget then

I'm in East London btw. I assume you're UK based?
Cheers!

 

Very interesting all around. Thanks fo all of the good links posted. I have been thinking about a similar project for some time, so that I can keep my (older) laptop charged up while traveling. Lots of fast food places have free WiFi but many do not have any AC outlets available. So 19 volts should keep it happy even if I use it from inside the car. Unfortunately for me, it is much more likely that I will try to build some version of a step-up module instead of buy one ready-made. I can start with what I have, which is one that delivers 12 volts at up to ten amps, from a 24 volt supply. It was originally used to power a 12 volt transceiver in a 24 volt system "big truck." unfortunately the manufacturer will not provide any circuit information so I will need to trace it out and see how it works.
Lambda products have always been very high quality, so no issue there, but they are also high priced. But with them you do get what you pay for.