|Product Performed to Expectations:||10|
|Specifications were sufficient to design with:||10|
|Demo Software was of good quality:||10|
|Product was easy to use:||10|
|Support materials were available:||10|
|The price to performance ratio was good:||10|
|TotalScore:||60 / 60|
Let's begin with what this board is, and what isn't. PMLK-BUCK board is an education material for college students. It is two different type of DC-DC converters on one board, with all the relevant test points exposed with metal loops for easy probe attachments. It is not really useful as a general purpose DC-DC converter as its voltages are fixed at 2.5 and 3.3 Volts and the board is much bigger than it needs to be.
Out of the box came the board, but it is not much of a use without its manual, found here.
The manual begins with circuit schematics, detailed description and bill of materials. Then it proceeds to a set of experiments. For each experiment, first there is theoretical summary, followed by "good to know" information. Then It shows test diagram. The diagrams are followed by detailed step by step setup instructions, and finally the actual test assignment. The instructions are concise and to the point. If you read all the steps carefully, you can do the experiments without confusion. The diagram for the first experiment looks like this:
Doesn't leave much room for confusion, although a bit crowded. I would have preferred simplified symbols for all the supplies and measurement equipment instead of photographs, but this is not really bad in any way.
The board itself has screw terminals for input and output. Several options (like capacitor values) are settable with jumpers, and the board comes with more jumpers than it will be needed. A simple detail, but well thought out. There are two circuits on one PCB, one with an LM3475, and one with TPS54160. The board feels sturdy and durable in my hand.
As seen in the photograph, the test points are conveniently broken out with metal loops, so both oscilloscope and voltmeter/amperemeter probes can be attached easily. Another cool feature is the large 0.01Ohm resistors on both circuits. It is R1 in the schematic below:
Since this is a low tolerance (1%) resistor, measuring the voltage over this resistor will give the current running over this resistor (divided by 100, obviously).
There are 6 experiments in total, followed by tests to check if we got the point. Although it is made for educational institutions, things are laid out clear enough that it can used for self study, provided that we have all the needed measurement tools. Most experiments require two voltmeters and two amperemeters to measure all input and output characteristics, which might be a bit too many, but it is easy to work around. Overall it is a helpful tool to learn about internal workings of buck converters, and how different parameters affect internal workings of the device.
I was slightly disappointed by the fact that output voltages are not adjustable, and they are below 5 Volts. I would have loved to play with it by supplying power to my Arduino boards and servos and see effects of more complex loads. However, this is outside the scope of this kit. At roughly €50, it is an aptly priced learning tool.