Custom Bucking Regulators

I saw on the product page for a few of the buck converter families that their output & efficiency can be tweaked for a custom order. I have a few questions on that front but first, some info about my application.

I’m looking at picking up a few pieces from the D36V28X, D36V50X, and/or D36V28X families and my input will always be roughly 12V. I need a few mostly standard voltages (5, 6, 7.5) but also need an odd one at 8.4V (beefy RC servo).

With that said:

  1. How much more peak efficiency could I expect from the 20V mosfet swap for each of these families?

  2. How much more would they cost?

  3. How much lead time is required?

Tried reaching out by phone and email and haven’t gotten a response in several days, which is odd as I recall Pololu being pretty prompt on support in the past. Figured I’d try here as well.


Sorry we did not get back to you quicker. There’s not much to gain from the MOSFET swap at your operating points, so I think it would only be something to consider if you were looking at getting thousands of units or we were constrained on the normal MOSFET we use, which at the moment we are not.

For the servo voltage customization, I suspect that is also not practical or worthwhile since we also have 9V versions of the regulators as stock products. If the 8.4V max is a nominal voltage (e.g. for use with 7-cell NiMH pack), that has to handle above 9V anyway, and if the 8.4V is a real max (e.g. for 2s lipo use), 7.5V should be appropriate.

A minimal customization will typically start at a few hundred dollars for setup, and it’s generally intended for customers looking to get at least several dozen units but typically hundreds or thousands of units. Usually we can do it within 1-2 weeks, but for higher quantities the lead time can be longer.

By the way, we just released this new family:

Those might be best for 12V input, unless you need the higher current that the bigger D36V50x can do.

- Jan

Hi Jan,

Thanks for your response and email regarding customization. That answered my questions pretty well, however I came up with a follow up question that hopefully you can answer.

In addition to having multiple voltages I also have a variety of loads including several Servos of a few different sizes, an MCU, SBC, Display, and quite a few COB HPLEDs. For loads of the same voltage requirements, is it generally a good idea (for the purpose of mitigating noise) to try to distribute the loads across several VRs? That is, should I try to balance the loads across a few D30V30F’s or a single D36V50F

Using multiple regulators is probably a bit better overall, but it depends on what you are trying to optimize for and what your particular loads and available regulators are. Two of the D30V30Fx regulators will generally give you a total current a little over the current of a single D36V50Fx regulator, and at the moment the price for two of the smaller regulators is just over the price of the bigger one, but that is not always the case. The single larger regulator gives you more flexibility if your loads don’t conveniently split into something you can cover with multiple smaller regulators. Which approach has the advantange in terms of overall physical size or wiring complexity will depend on the details of your project.

The multiple-regulator approach gives you the benefit of separating systems so that they are less likely to interfere with each other, which could be a big deal for troubleshooting or reliability. Separating the regulators also gives you more modularity and flexibility for changes you might make down the road. For instance, if you want to add servos and have a power supply just for them, you just have to get a bigger servo supply and don’t have to change any of your main controller power.

Different loads might also handle voltage fluctuations very differently. Maybe you have a bunch of servos that might occasionally all strain at the same time, and if the supply voltage drops a bit and the servos have a corresponding fluctuation in torque, that could be totally fine. But if you have a controller on that same supply, a drop in voltage could be a much bigger deal if it causes the controller to reset.

- Jan