The first thing to say about this board is that the output is via a regular USB port, but it outputs the full voltage from USB-C PD (up to 20 V). In other words, DO NOT PLUG ANYTHING INTO THIS USB PORT THAT IS EXPECTING A STANDARD USB VOLTAGE. You will damage it, and you might set it on fire. Why the designers chose this as an output connector, rather than having a barrel jack, is a mystery to us.
That warning in place, let’s take a look at what the module actually does. There are both male and female USB-C ports, but they both work in the same way, and you can supply power via either one. Having both is handy, as it means you can connect it directly to either a computer or a power supply. Once the board is powered up, the three seven-segment displays light up, displaying the voltage. There are two buttons on the board: one requests a higher voltage, the other a lower voltage. These allow you to scroll through the available power profiles.
In this usage, you can select the power you need for your project and get it to come through a compatible USB-C device. In theory, it can supply up to 100 watts (20 V, 5 A); however, we would have some concerns about running this much power through the device. If you want to push the limits of USB-C, then we’d strongly recommend a module from a reputable manufacturer (there’s not even manufacturer’s information with this board).
This module works well for prototyping, but it would be nice if there was a way to set the voltage a little more permanently. It does remember the power profiles between power-offs, but if anything taps the button, it’ll shift the power. In principle, you could remove the buttons once you had the power profile you want selected. It would also be nice if there were a digital interface to this so you could interact with it from a microcontroller, but we’ve only seen this capability in more expensive boards.
If you have a spare USB-C power supply, or USB-C portable power bank, this is a cheap way of accessing its power modes for prototypes, but you’ll probably want a more robust solution if you’re planning on using the power for any length of time.