This article is based on the Japanese version of Engadget and was created by machine translation.

The lineup of USB charging cables sold at 100 yen shops is surprisingly extensive, and many products (including anything suspicious) are sold. USB Type-C cables have been around since last year, but when I noticed, there were more Type-C conversion cables and adapters. So, what's interesting is what's inside. I decided to take it apart and see what's really going on.

Purpose of the experiment

There are many cases where the information on the package is insufficient, so the purpose is to confirm the truth.


USB Type-C is a confusing standard because it's used in USB 2.0 as well as USB 3.1, and it's also used in Thunderbolt 3. There is also a power supply standard called USB PD, which is fueling this confusion.

In a nutshell "The USB Type-C connector is just a shape of a connector.", it doesn't matter what kind of communication it supports or how much power it has, but few people know it perfectly. If you ask the manufacturer if they understand the product perfectly ...... it's not true. Overseas, for example, Benson Leung of Google has been known to have tried every USB Type-C cable he could find and then trashed it on

There are a lot of tests in Japan, and Masahiro Yamaguchi's article on how smartphone charging cables work is excellent. It is very helpful because it is widely checked from the manufacturer's products to those sold at 100 yen shops. If you read "PC Power Supply Edition" at the same time, you will understand more.

USB Type-C is a mix of standards. Exploring the behavior [Smartphone Edition]

USB Type-C is a mix of standards. Exploring the behavior [PC Power Supply Edition]

また、If you want to focus on USB AC rather than USB Type-C cable, check out Hanpen's review at If you're considering buying an AC adapter as well as a cable, it's worth reading. Previously, all of his reviews had been removed from, but now they're back. Good.

Amazon review by Hanpen

That's why the world's USB Type-C devices are a mixture of good and bad, but this post is a bit different from the practical tests.

It was a very simple start, and right after the launch of the Nintendo switch, people started saying that "With 56 kΩ resistance" was a requirement for something that could be used as a charging cable. I didn't feel anything from people who were familiar with and tinkering with gadgets on a regular basis, but I was intrigued by the fact that I heard those words from the light group, who didn't care about resistance and didn't even know they existed.

That's probably what Nintendo wrote. The switch Q & A clearly states "When connecting with a commercially available USB cable, use a cable with 56 k registers (resistance) mounted."

"By the way, where is the resistance? Built-in connector? Board mounted? Type-A side? Type-C side?"

I cared about it to the extent of thinking so, but I forgot about it.

I remembered that when I noticed a slight increase of USB Type-C related products at 100 yen shop (Daiso) the other day. There was a short 10 cm USB Type-A/Type-C cable, USB Type-C to USB Type-A adapter, and a suspicious USB Type-C/Type-C cable.

Somehow, I picked up the cable package and looked at the back, and found nothing about resistance. I thought it was a hot topic, but it's still not specified, so I'm starting to wonder if there's really no resistance to this product.

Also, when I take the conversion adapter package in my hand and look at it carefully, the terminal is blue. It's hard to see it in the package, but it looks like there are 9 terminals. This is not specified, but is it USB 3.0?

Anyway, the package doesn't have good information and I can't see anything I want to know. All right, I thought I'd check it physically, so I decided to take it apart.

Experimental object

The researchers tested a 10 cm cable labeled "High-speed charging and communication cable USB > > Type-C", an adapter labeled "Conversion AdapterUSB > > TypeC", a 100 cm cable labeled "High-speed charging and communication cable Type-C > > Type-C", and a micro USB adapter that I found later that said "Type-C Conversion Adapters". These four products are all sold at Daiso.

▲From left to right: 10 cm USB Type-A/Type-C cable, USB Type-A/Type-C adapter, USB Type-C/Type-C cable

▲I found the adapter after disassembling the previous 3 products, so I added it in a hurry. It is an adapter to convert the micro USB terminal often used for cables of smartphones to USB Type-C terminal.

Experimental method

There is no experimental method because it is a disassembly, but it is a simple one that disassembles and introduces the board if there is a board and the connector if there is only a connector. If there is resistance, the resistance value is also measured.

I used scissors, cutters, nippers, protective glasses, leutors, multimeters, etc. This is a common tool (It will be.) in your home.

▲The case of the USB Type-A/Type-C adapter was made of aluminum, so I cut it with a leutor. Other than that, I can manage with a nipper and a cutter.

▲I used a previously purchased multimeter "OWON B 35" to check the resistance. It is cheap but very convenient, so I am using it regularly.

Experiment 1 "High-speed charging and communication cable USB > > Type-C"

Let's start with "High-speed charging and communication cable USB > > Type-C" which is 10 cm short but common as a charging cable. First of all, from the appearance of the product.

▲It's short, but it's a very common charging cable. When you use a smartphone while charging with a mobile battery, this shortness is appreciated.

▲The key is the mesh cable which is resistant to pulling and hard to break inside. 10 cm doesn't seem to mean much.

It feels like a decent cable. But it's about appearance. You can't tell if it's working properly without checking to see if it has an unmarked 56 kΩ or if the cable is thick enough to accommodate the 3A current.

So, take it apart and check.

▲On the USB Type-C side, one side has a cable connection, and the other side has a resistor and a capacitor. The value of this resistance is about 55.7 kΩ. It was solid.

▲There was no board on the USB Type-A side and the cable was directly connected to the connector. The 5V and GND lines also look solid.

As you can see in the photos, it has a solid 56 kΩ (55.7 k ohms.) resistance, plenty of cable thickness, and seems to support fast charging. Also, although it was solidified with resin, it had a double structure where it was first solidified with translucent resin and then solidified with the surrounding pink resin. I don't know the merits, but I'm sure it's carefully made.

If you want a short 10 cm charging cable, it will be very useful.

Experiment 2 "High-speed charging and communication cable Type-C > > Type-C"

Next, both ends are shaped like USB Type-C "High-speed charging and communication cable Type-C > > Type-C". I will check it from the appearance of the product.

▲The USB Type-C cable has no special features and is hard to comment on. It's 100 cm long, so you can charge it from your mobile battery in your bag.

It's a boring cable that is characterized by its uncharacteristic appearance that makes it difficult for the manufacturer to make a catch copy. I only have the impression that there was a little bit of burr. At first, I thought it was 50 cm, but when I looked at the package carefully, it was 100 cm, which was the only surprising point.

Let's take a look inside.

▲I cut the power line a little with a cutter. the degree to which something may be a little thin. There was no resistance, just a capacitor.

It's a charging cable, but there's no resistance. I shaved both ends just in case, but both of them were just capacitors. If both ends are USB Type-C, it means that both ends are connected to USB Type-C compatible devices, so it doesn't have to be marked on the cable side? I don't know if this is common.

As a test, I plugged a Moto Z2 Play into a USB Type-C laptop (I can't name it for some reason, but it's a BTO PC with 8th generation Core i7.) and it was rechargeable. The display on the screen also says "TurboPower Connected", so if both are connected to USB Type-C, there's a good chance you can use it without problems.

▲The combination of the laptop and the Moto Z2 Play allowed for fast charging. It may be unexpectedly good.

Considering the length of the cable is 100 cm, the power line seems a little thin, but it is thicker than the signal line, so it seems to be considered properly. However, the package says 5 V 2.4 A, so if you use it for charging, you should use it only for a smartphone, not for a tablet, laptop or other power-consuming devices.

Also, communication is possible, but since there are only 5 wires, communication is possible only by USB 2.0.

Experiment 3 "Conversion AdapterUSB > > TypeC"

The third is an adapter, not a cable "Conversion AdapterUSB > > TypeC". When I read the description of the package, it said that it was an adapter for charging and communication, but this is not generally used for charging, but it is an adapter for connecting USB devices such as mice, keyboards and storage, so-called OTG (USB On-The-Go, USB Host) ......。

In any case, it doesn't have to be USB 3.0 for charging purposes, so it uses a connector that looks like USB 3.0 at first glance, but it's possible that there are only four wires inside.

▲This adapter is made of aluminum instead of resin, so it looks a little different from the one sold at a 100 yen shop. It seems to be for charging and communication, but ......

▲The blue connector appears to be a good enough USB 3.0. If you take a close look at the terminal, you can see that 5 pins have been added to the front.

I was going to disassemble it and check the contents, but the aluminum exterior cannot be cut with a nipper, so I used a leutor.

▲It says "USB 3.0 - OTG" firmly on the board! You can say it is definite. The backside resistance is 5kΩ. I am concerned that R2 is written on the capacitor.

As expected, the board inside is clearly marked with the word "USB 3.0 - OTG" which makes it more likely that this is an OTG adapter. If you look at the backside, you can see that it has a resistor and a capacitor. When I checked the value, it was 5kΩ, so this proved to be an OTG adapter.

To verify operation, I used a laptop with USB Type-C and USB Type-A (Both are USB 3.1), connected external storage that converted an old SATA SSD to a USB 3.0 connection, and examined whether the speed changed with or without the OTG adapter.

▲I checked the speed with Crystal DiskMark. The one on the left is via "Conversion AdapterUSB > > TypeC" and the one on the right is directly connected to USB Type-A. The speed is almost the same. But, the SSD is old, so it's slow.

The results are pretty much the same. It's slow because there's no fast storage for testing and I pulled out my old SSD, but it's still way above the 60 MB/s theoretical value for USB 2.0, so I'm sure it works with USB 3.0.

One more thing by the way. This is OTG, which means it's likely to work on smartphones. I plugged the adapter into the Moto Z2 Play and connected a mouse, and the cursor appeared. I could operate without any problem.

▲With OTG, you can connect USB devices to your smartphone. It's a little hard to see, but I wonder if you can see the mouse cursor on the screen of my smartphone.

It's hard to understand why they're selling it as a charging and communications adapter, even though they should be selling it as an OTG adapter, hiding the fact that it's USB 3.0. Of course, you can charge it, but ......。

Experiment 4 "Type-C Conversion Adapters"

Finally, there's the "Type-C Conversion Adapters" for converting from micro USB. Actually, I found this adapter and disassembled it before, but I didn't see it in the store after that, so I thought it was sold out. But this time, it was discovered accidentally after the above three products were disassembled. I added it to the test immediately.

▲A common adapter for converting micro USB to USB Type-C. something that is very small and simple.

The adapter is small, less than 2.5 cm in length, and it doesn't have any special appearance. Let's take a quick look inside.

▲Of course, there are no cables and the connectors are directly on the board. with a capacitor and a resistor on one side.

It's simple inside, with USB Type-C and micro USB connectors on each end of the board. On one side, there was a capacitor and a resistor, and when I checked the resistance, it was about 56.3 kΩ, which was a decent adapter for charging. If you plug the adapter into an existing micro USB charging cable, you can turn it into a USB Type-C charging cable with 56 k resistance. If you have both micro USB and USB Type-C devices, this is a handy adapter.

Conclusion and Summary

So to summarize what we've learned from this experiment:
  • 1. 10 cm charging cable is practical
  • 2. Type-C/Type-C cables are somewhat suspect
  • 3. OTG adapter is worth buying
  • 4. The micro USB adapter has resistance and is decent

I guess so.

Especially, the three products except for "High-speed charging and communication cable Type-C > > Type-C" were higher in quality than I expected, and in a good way, I was disappointed. But why is the package so unfriendly? If they could improve that point, it would be a little easier to buy. But if you want that kind of product, you should buy the product of the proper manufacturer.

USB Type-C is often difficult, so unless you know it, you shouldn't buy dubious products. On the other hand, if you can handle it on your own, you can find something cheap and good. Personally, I was impressed with the 10 cm cable and the OTG adapter.

This article is based on the Japanese version of Engadget and was created by machine translation. The Japanese edition of Engadget does not guarantee the accuracy or reliability of this article.