An interesting cable and breakout board for installing converter modules from YZXstudio

As I mentioned, I’ll be reviewing a cross-board for installing converter modules soon. I ordered it from the same Taobao store as the converters themselves, and it seemed interesting enough to deserve its own review.


The store page offers not only the circuit board, but also an enclosure, front panels, and panel options with an XT30 connector.


In my case, I got the board and a cable, though the cable is a separate listing. I’ll talk about it today too.
The little bag of some kind of tiny inductors made me smile :)


It looks very neat. The manufacturer’s name is on both sides of the board: on top as tinned copper polygons, and on the bottom printed in ink.


The board is very compact. Its width is about the length of a standard matchbox, though its actual dimensions are 60x50 mm.


Connectors are installed on one side. In my configuration, these are USB Type-C and a round 5.5/2.5 connector, with space for an XT30 to the right.


Here’s what I was interested in on this board: the controller, whose marking I couldn’t make out in the store photo.


The controller, IP2721, is needed to request the required output voltage from a charger using the Power Delivery 2.0 or 3.0 protocol. There are two versions of this controller: one supports voltages up to 20 V, while the other supports only 12 V. This board has the first version.



You can install any of the converters shown in the photo on this board, in any combination. If you install a ZC826 board and connect a 4S battery (16.8 V) through the XT30 connector, you can even build a universal power supply with a power bank function; charging will also go through the ZC826 board. The only downside is that you’ll always have to charge the battery through this board. Also, the output voltage of the other installed boards (unless they’re also ZC822 boards) will be limited to 12–15 V.


Since I have other plans for the ZC826 board, I decided to try installing a ZC822 board and a pair of ZC823 boards: one rated at 60 W, and the other also at 60 W but advertised as 100 W.


It turned out pretty well. Just a reminder: the 822 and 823 boards each have two connectors, while the 826 has only Type-C.


I just tacked the boards in place; I didn’t solder them permanently because I’m not yet sure how the whole thing will look in the end.


You can either buy an enclosure for all this and end up with a setup like this, or make one yourself from whatever materials you have on hand.


Before the tests, a few words about the cable. It’s not as simple as it looks at first glance: it appears to be a regular Type-C cable on one end and a round 5.5/2.5 plug on the other.


It costs a little over two dollars. It’s available on AliExpress too, but costs almost twice as much there. There are several options: 20 V output, 15 V output, and a 100 W version that’s 20 cm long and also available for 20 V or 15 V.
Taobao link
AliExpress link


The idea behind the cable is that when you connect it to a charger’s Power Delivery output, you automatically get 20 V at the other end, as shown in this photo.



What’s more, even if you just connect the cable to the charger’s output, the charger starts up and automatically switches to 20 V mode. For some reason, though, the tester shows the QC 2.0 protocol in this case.


I unplugged this handy cable and connected the cross-board with a regular Type-C-to-Type-C cable. The result was about the same: the charger automatically switched to 20 V mode. I think there’s the same chip inside the cable as on the board.


But I noticed an interesting quirk. It initially outputs 20 V, but the protocol shown is Apple. If you touch any of the power wires, it starts showing the QC protocol.


In the end, I got three different protocol readings:
1. Don’t touch anything — DCP1.5A
2. Touch any wire — QC 2.0
3. Just hold your hand near the wire — Apple

In this case, I powered the board from a linear power supply, since I had previously suspected interference from a switching power supply.

4. The tester has a switch for the Power Delivery control contact: in one position, control comes from the tester; in the other, from the load. If you select control from the tester, switching does not happen. When the cable is connected directly to the charger, switching always works correctly.


The board can easily be powered from a regular 24 V power supply. In principle, the supply voltage matters only for the maximum output voltage of the converter boards (822 and 823); for board 826, it makes little difference because that board is universal.
But I recommend a voltage of 20–24 V. One option is 19 V from a laptop power supply, though that can cause problems because boards 822 and 823 won't output 20 V.


And here's one example of using a cable with a built-in protocol controller. A soldering iron is connected to the charger's output, so the charger supplies 20 V.
This example is a bit of a stretch, since in this particular case it would be easier to power it directly from a power supply. But this setup does let you power the soldering iron from a mains power supply with Power Delivery and an output of at least 50 W.


If the charger can output 20 V, that's what you'll get. If it can't, you'll get the highest voltage it can provide. For example, this board supports only 12 V, so that's what it outputs.


All in all, I think both products are interesting: the board and the cable. They cost about the same, and both have a chip that controls the charger, but functionally they're quite different, of course.
Honestly, I'm not even sure what to say. It's curious, interesting, and very useful in some situations.

Thanks to my reader Vladimir for sending me the cable and board—and, of course, for providing the material for this review :)