Hi!
Im lookin for a DC/DC Step-Up, from 12V to 19,5V.
Will be fed by a LIFEPo4 battery, and will be powering a LG Monitor with a Power requirement about 140W. Do you have a recomended product?
Hello fredrik.wickstroem,
Welcome to the DigiKey TechForum.
I presume these are off board type converters you’re after. I could not find any at near that input with 19.5V output or about, and none that had that low input and 140W output that we carry.
You can review some options in our DC DC converters below by filtering the necessary parameters.
DC DC Converters | Power Supplies - External/Internal (Off-Board) | DigiKey
Hejsan @fredrik.wickstroem ,
You could also consider using an inverter and LG’s own AC adapter. May be a bit less efficient though.
https://www.digikey.com/en/products/detail/mean-well-usa-inc/A301-150-F3/7702523
Cheers, heke
19.5V is a voltage that is common for monitors and laptops, but is rarely seen in off the shelf power supplies. To get the voltage you will need to use either a power supply from the manufacturer or find a power supply with an adjustable output voltage.
A 140 W monitor at 19.5 V requires about 7.2 A output. Allowing for converter losses, the 12 V battery could supply 13–15 A, so I would choose an adjustable boost converter rated for at least 180–200 W continuous rather than exactly 140 W.
Also check the monitor connector polarity, use suitably thick wiring and a fuse near the battery, and ensure the converter has low-voltage cutoff suitable for a 4S LiFePO4 pack. A 150–180 W automotive laptop adapter with an adjustable 19.5 V output could also be a practical option.
This boost-converter design is a useful reference for the 12 V-to-laptop-voltage topology, although its 4 A output rating is insufficient for this 140 W monitor. A commercial converter rated for at least 7.2 A at 19.5 V, with additional headroom, would still be required.