An ode to buck-boost DC power converters

Ben Stein

Ben Stein

Publisher of, passionate marine electronics enthusiast, 100-ton USCG master.

20 Responses

  1. Interesting – and the price is certainly right! Have you experienced any RFI from these switching power supplies?

    • Ben Stein Ben Stein says:

      I haven’t had any RFI issues from them. I have two of them pretty close to the head unit and wiring for the stereo amps. I’d think if there were much noise that may well be a good indicator.

  2. I’ve used these a bunch on the boat and had mixed experience with various vendors. I am mostly trying to convert 12v to 5v for powering devices like an Amazon Echo, Raspberry Pi, etc.

    None of them have stood the test of time – they all have stopped working at some point. And I did have a high quantity of out of box failures for some of the DROK ones. However, I have one now from Binzet that has lasted longer than any others, is quite a bit bigger, doesn’t get super warm, and hopefully will last!

    • Ben Stein Ben Stein says:

      My sample size is pretty small. I think I have 7 in use on the boat right now. I’m happy to say (and knocking on wood) I haven’t had one fail. I’m also using all stabilizing types, not step up or down. I wouldn’t be surprised if one type or another failed more frequently.

      • Ah yes, voltage regulator type converters are going to have less work to do than 12v-5v step down ones. I also tried a few step up converters for PoE systems from 12v-24v and 12v-48v and they were even worse, which makes sense since they are doing far more “work” in that mode.

  3. Antti N says:

    We use these a lot at work, and I have just one advice:

    Always invest a bit extra to get a quality unit, price different is relatively minor compared to other costs in boat. We always use Phoenix Contact when it is critical job, they are the best you can buy, but come with a pricetag. Second tier is likes of Meanwell and Mascot, still good and solid units. Cheaper than that make good paperweights.

  4. Ben Ellison Ben Ellison says:

    I notice that are some reasonably priced, lower current, marine grade DC/DC converters if your needs are different than the 12v/12v stabilization Ben Stein requires. Especially if you want to step down from a 24v boat system for devices that insist on 12v (like NMEA 2000 networks):

    Unfortunately, though, I don’t see a small 12v to 24v converter available from any marine brand, but maybe I missed something?

  5. The really annoying part of this whole thing is that 24V is really not necessary here – it’s present solely to power the POE port of the Ubiquiti router, and the Bullet it’s powering will work fine on 12 (or even 8) volts! (because it regulates it down to 5V inside). The “cost” is probably only a few dozens of milliamps, but it’s just so unnecessary!

  6. Ben Stein Ben Stein says:

    Hartley, the best I could find for the Alfatronix products was a listing showing a 12-24 step up for 111 pounds out of the UK, that’s right around $150.

    But, this caused me to wonder whether something else could be found reasonably that would provide better quality. It turns out Victron Energy makes some products in this range.

    They’re not as inexpensive as the Amazon sourced buck-boost pieces. The 8a continuous and 20a surge load model is available from PKYS for $63.75.

    There’s also a 12-12v converter / stabilizer that I will try if any of the current units I have fail. Again, it’s not as affordable but not bad at $64.60 for the 9a model.

    • Hi Ben, Not a surprise, really. For this task, since I’m trying to keep my total system cost (for a MiFi/hi-powered WiFi – based Internet system) below that $150 figure, these aren’t candidates for me. If I needed 6 or 8 amps at 24V, $65 is not unreasonable at all, however.
      IMHO, the most efficient course is to avoid the need for voltage conversions at all 🙂

      • If you’re powering a Ubiquiti Bullet that supports PoE (as most of them do) take a look at Tycon systems. I use several of these for PoE devices on Grace including a Bullet and a MikroTik:

        They convert 12v to 24v PoE and have ethernet ports built right in. You can find them for cheaper elsewhere online, but Amazon has them for those who need them quickly. They last a long time, and I’ve used them both on the boat and in remote solar projects in pretty extreme conditions.

  7. Saffy The Pook says:

    I’ve had good luck with the SMAKN-branded flavor of those Chinese up- and down- converters. I’ve had a 12->48V unit powering my Ubiquiti Toughswitch 8-150W for over a year continuously and a 24->12V unit as part of a lithium ion BMS for over a year continuously as well. No noise or performance issues at all.

    • Ben Stein Ben Stein says:

      I believe several of the units I’m using are SMAKN as well and as I’ve mentioned I’ve had good luck with them. I also did cruise through the reviews of a few different units and they seem to generally be either very positive or immediate/near-immediate failures.

  8. Dan Corcoran says:

    I have a friend that obtained stabilization another way, to present instrument reset on sailboat engine start. He inserter a 2 Farad capacitor (like you use for supporting loud stereo base in an auto) and diode to the source side of the DC panel for only those instrument circuits you want to protect. There should be enough resistance between there and the battery to not require a 1 ohm resistor (to charge cap).

  9. Colin A says:

    Mastervolt at least used to make one. I only know because there is one sitting about 20′ from me. Meanwell I belive also makes some but not marine rated.

    Found the Mastervolt that I had sitting around

  10. I installed the CarNetix CNX-P1900 Dual Output 140 Watt 12V DC-DC Regulator about 10 years ago to run our navigation PC and 12Vdc monitor while cruising Mexico.. Although it’s intended for the automotive market, it has performed well over the years for us with no failures. Just thought I’d add it to the discussion mix. It’s available from and Amazon.

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