NAM 0.3 powered by 12V or more

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From the very beginning, NAM 0.3 required 5V voltage to operate, as this is the supply voltage required by SDS011. The simplest solution was to use a 5V power supply, which is what we did. However, with the arrival of NAM-0.4, which can be powered by a voltage ranging from 6.7V to 20V thanks to a step-down module, questions arose as to whether 0.3 could also be retrofitted in this way.

In the future, there may be a version with built-in support for such a power supply option, but even today, it is possible to easily modify the NAM to work with a higher voltage.

The NAM 0.4 uses the MINI560 (JW5068A) step-down module for one simple reason – this module is “fixed” at 5V, nothing needs to be done with it, just power it up and you have 5V. That makes it easier to build whole device.

However, there is another option: step down with MP1584EN. It is also low-profile, so it fits under the SDS, and the input voltage can be as high as 28V. If you need to power the NAM from 24V, this step-down will be just right. The only “inconvenience” is that you have to adjust the output voltage with a potentiometer so that it is 5V. In the case of MINI560, this step is not necessary.

What else will you need? Of course, some wires and a 2.1/5.5 panel power socket.

I will show the conversion using the example of a ready-made, already soldered NAM. If you do it at the soldering stage, you will probably be able to do it a little more neatly. For example, do not solder the 2.1/5.5 socket for 5V – first of all, you will not be able to make a mistake in the future and plug a 12V plug into a 5V socket. Secondly, you will be able to easily solder the wires from the step-down module to the holes instead of the socket.

Stick the step-down module under the SDS011 using our favorite hot glue. Look at it carefully first to know which side is the input and which is the output. The description is basically only on the bottom of the PCB. This applies to both the MINI560 and EN1584EN modules…

The second step is to drill (with an 8 mm drill bit) a hole for the panel socket. It is a bit short, so you need to tighten the nut properly and there is no chance of installing the spring washer. The mounting is quite secure. All NAMs up to and including 0.3.2 had this type of power supply solution, so I would not be concerned that it would not hold well.

All that remains is to pick up a soldering iron, cut the wires, and solder the plug to the step-down module input and solder the output to the 5V socket. As you can see in the photo, doing this at the soldering stage and giving up the 5V socket will greatly simplify the whole operation.

And that’s basically it – from now on, you can power the NAM with a higher voltage. From experience, I would add that if you are modifying an already built NAM 0.3.3, be sure to block the 5V socket (9-pin barrel). Hot glue will do, or anything that will prevent mistakes and connecting, for example, 12V to the 5V socket.