CIO 100W USB-C GaN Review



CIO 100W USB-C GaN - Nearly the size of a MacBook Pro power adapter, with more power, USB ports, and fast charging options


The CIO 100W USB-C GaN reaches the limits of USB-C output but doesn’t stop there. It also supports newer and old fast-charging standards and can handle 2-3 devices at once. While being no larger than your laptop’s current single-port charger.

  • Performance
  • Design
  • Safety
  • Portability
User Review
0 (0 votes)


  • Fast charges iPhone, Samsung Galaxy, Google Pixel, LG, and Motorola phones
  • Charges Switch while you play
  • Fits in most Switch carrying cases
  • Charges up to a 16-inch laptop
  • GaN tech
  • Travel-friendly design
  • Fast charges three devices at once
  • Works worldwide with 100-240V power input (may need a plug adapter)


  • Third USB-C port and USB-A port share a circuit, limiting output
  • Not compatible with Nintendo Switch’s dock
  • Quick Charge 3.0 over USB-C is against USB-C specs
  • Doesn’t include a USB-C to USB-C cable, and wants a 5A cable for optimal output

Disclosure: As an Amazon Associate I earn from qualifying purchases. CIO provided the product in this review.

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[wpcd_coupon id=12311]
Model: CIO-G100W3C1A
Tech Specs:
  • Ports: USB-C x3, USB-A
  • USB-C 1 & USB-C 2 Output:
    • 100W USB-C Power Delivery 3.0 (5V/3A, 9V/3A, 12V/3A, 15V/3A, 20V/5A)
    • PPS (3.3-21V/5A)
    • Quick Charge 3.0
    • Samsung Adaptive Fast Charging
    • Huawei FCP
    • Apple 2.4A
  • USB-C 3 Output:
    • 30W USB-C Power Delivery 3.0 (5V/3A, 9V/3A, 12V/2.5A, 15V/2A, 20V/1.5A)
    • PPS (3.3-21V/3A)
    • Quick Charge 3.0
    • Samsung Adaptive Fast Charging
    • Huawei FCP
    • Apple 2.4A
  • USB-A Output:
    • 30W Quick Charge 3.0
    • Samsung Adaptive Fast Charging
    • Huawei FCP
    • Apple 2.4A
  • Multi-port Output:
    • USB-C 1 + USB-C 2/USB-C 3/USB-A = 65W + 30W
    • USB-C 2 + USB-C 3/USB-A = 65W + 30W
    • USB-C 3 + USB-A = 15W shared
    • USB-C 1 + USB-C 2 + USB-C/USB-A = 45W + 30W + 18W
    • USB-C 1/USB-C 2 + USB-C 3 + USB-A = 65W C1/2 + 15W shared between C3 and A
    • USB-C 1 + USB-C 2 + USB-C 3 + USB-A = 45W + 30W + 15W shared between C3 and A
  • Input: 100V–240V, 50/60Hz, 2.0A
  • Size: 3 x 2.4 x 1.1 inches | 75 x 60 x 29 mm
  • Weight: 7.6 oz | 214 grams

Learn more about Fast Charging.

Included In Box:
  • CIO 100W USB-C GaN
CIO 100W USB-C GaN box and contents

CIO 100W USB-C GaN box and contents

Good For:
  • Additional charger for home or work
  • Commute
  • Travel
  • iPhone
  • Android
  • Power banks
  • Nintendo Switch (handheld & docked)
  • iPad Pro
  • 12-inch laptop
  • 13-inch/14-inch laptop
  • 15-inch laptop
  • 16-inch laptop

First Impression

The No products found. gets some space savings through its GaN tech, but not as much as lower output chargers. That is typical, as the returns on GaN start to diminish past 60W. Still, this charger is smaller than my 13-inch MacBook Pro’s 61W power adapter. With 40% more output, three extra ports, and a lot of fast charging standards.

Plugged into a wall outlet, you’ll want it on the bottom, as it drops well below the plug itself. It’ll take up almost as much space as your current laptop charger. The real space savings comes if you can replace two or more chargers with this one.


Compared To Similar Chargers

ChargerNo products found.Anker PowerPort Atom PD 4No products found.Satechi 108W Pro USB-C
PortsUSB-C x3, USB-AUSB-C x2, USB-A x2USB-C x2, USB-A x2USB-C x2, USB-A x2
Output100W USB-C PD

30W Quick Charge 3.0 USB-A

100W max total output


100W max total output between USB-C ports


90W max total output between USB-C ports


FeaturesGaN techDesktop chargerGaN techDesktop charger
CableNo cableNo cableNo cableNo cable
Dimensions3 x 2.4 x 1.1 in
7.6 oz
4.1 × 3.3 × 1.3 in
13.5 oz
2.8 x 2.7 x 1.3 in
7.9 oz
4.8 x 3.1 x 1.2 in
14.7 oz
PriceNo products found.Price not availableNo products found.$79.99

Prices are from Amazon Product Advertising API, last updated on 2023-09-29.

You can see more USB-C chargers here.

Device Testing

Check with your device’s manufacturer to verify which charging standards it supports.

USB Power Delivery & Quick Charge 4+ Phones

  • Apple iPhone 8/X/XR/XS/SE/11/12
  • Apple iPad Pro
  • Essential Phone
  • Google Pixel
  • LG ThinQ/V30
  • Razer
  • Samsung Galaxy S8/S9/S10/S20
  • Samsung Galaxy Note 8/9/10
  • Xiaomi Mi 8/9
  • ZTE Axon Pro 9/10


Using an iPhone 8 for testing, we find USB PD phones will fast charge over the USB-C port. iPhones will need to use a USB-C to Lightning cable, not included. And Android phones will need a USB-C to USB-C cable, also not included.

For iPhones, the USB-A port supports Apple 2.4A. An older but still functional fast-charging standard. Older iPhones (4-7) can fast charge using USB-A. Newer iPhones will charge ~15 minutes faster using USB-C.

Quick Charge 3.0 Phones

  • HTC
  • LG
  • Motorola
  • Nokia
  • Samsung Galaxy
  • Sony
  • Xiaomi Mi 5/6
  • ZTE


Using a Moto G6 for testing, we see Quick Charge will fast charge over the USB-A port. The Moto G6 fails to get QC over USB-C as that is an issue with that particular model phone. Newer Motos and other Android phones would fast charge under the same connection.

Nintendo Switch


Fast charges all model Nintendo Switch in handheld mode.

  • Nintendo Switch (original) – Charges near its max rate while playing and sleeping.
  • Nintendo Switch (2019 update) – Charges near its max rate while playing and sleeping.
  • Nintendo Switch Lite – Charges near its max rate while playing and sleeping.

On spec it should work with the Nintendo Switch dock, but my testing shows it does not. The Switch’s dock is particular about its power sources. The variable offerings of the USB-C ports is likely causing the incompatibility. The issue lies with the design of the dock more so than anything else.

Learn more about charging the Switch.

USB-C Laptops


Using a 13-inch MacBook Pro for testing, we can draw up to 52W from this charger. Expected after accounting for efficiency loss.

Different model laptops have differing power demands. But in general, a 100W charger can support the largest and most power hungry laptops under any condition.

In multi-port mode the available 65W can support up to 13-inch/14-inch laptops under any condition. And 45W can support 12-inch, 13-inch, and 14-inch laptops. Either can power a larger laptop in a pinch, at worse slowing the battery drain.

Fast Charging Several Devices At Once

The multi-port fast charging is a great feature, but be sure you understand its limitations. You’ll need to use the right USB-C port with the right device to get the fastest charge possible for all your devices.

USB-C 1 and 2 will support up to 100W by themselves. USB-C 3 is limited to 30W, so a better option for phones, Nintendo Switch, tablets, etc.

Connecting with any two USB ports will drop the max output from 100W to 65W or less. So if charging your 16-inch MacBook Pro is top priority leave it be. But once its battery is at 80% you shouldn’t have a problem connecting your phone.

The bottom USB-C port and USB-A port share the same circuit. You can use both the USB-A port and either of the top two USB-C ports. But USB-C 3 and USB-A together disables all fast charging and shares a limited 15W output. You’ll want to avoid connecting four devices at once. Treat USB-C 3 and USB-A as an either/or setup.

Note that connecting a Lightning cable will cause that USB port to act as if a device is connected. Even if your iPhone/iPad is not on the other end. It is a known function of Apple Lightning cables.

CIO 100W USB-C GaN ports

CIO 100W USB-C GaN ports

PPS – Programmable Power Supply

Programmable power supply (PPS) protocol was added in USB Power Delivery 3.0. But not all PD 3.0 devices and chargers support it. It is uncommon now, but will grow in use. It allows for small, step-wise changes in voltage and current. This reduces conversion loss during charging. The power transfer is more efficient and lithium batteries endure less heat.

Under PPS charging occurs in two phases. In the first phase the current (amps) is constant, with a gradual increase in voltage. In the second phase the voltage (now at a higher state) is constant, with a gradual decrease in current.

Devices that support PPS include:

  • LG G7/G8 ThinQ
  • LG V40/V50 ThinQ
  • Razer Phone
  • Samsung Galaxy S10 5G/A70
  • Samsung Galaxy Note 10/10+
  • Xiaomi Mi 8/9
  • Any device supporting Quick Charge 4+

What does that all mean? If you have a PPS or Quick Charge 4+ supported device then this charger will fast charge it like any other USB-C PD. But will also put less stress on your device’s battery, increasing its lifespan.

If your devices don’t support PPS this tech will have no effect. You will be future proofed for a future PPS device.

USB-C Cable with 5A/100W Support

CIO’s 65W output requires a USB-C cable with an eMarker and support for 5A current. Such cables are not uncommon, but nor are they what you usually find with a simple search.

Most USB-C cables are only rated for 3A current. Limiting them to 60W power throughput. When a charger offering more than 20V/3A (65-100W) connects it checks the cable for an eMarker. The eMarker tells the charger about the cable’s capabilities. Such as increased power throughput. If it doesn’t detect an eMarker, then the charger assumes the cable is only rated for 3A current. In this case the charger will then only offer up to 60W.

So if you connect most any other USB-C cable you have to this charger it’ll limit itself to 60W. That’s fine if your device only draws 60W or less. Even if your device can draw 65W then missing 5W isn’t going to be noticeable. But if you want the full 65W you’ll need to get the proper cable.

Check out my USB-C cable listings for a suitable 5A charging cable

GaN (gallium nitride)

GaN (gallium nitride) is a replacement for traditional silicon. It can sustain higher voltages than silicon and offers less resistance to current. That makes it more efficient (10-25%) and able to handle more heat. In 2014 GaN performed the same as silicon 3-5 times larger. The most recent leap (2017) reduced the size of GaN transistors to half their previous size.

GaN is not new. It is in the laser diodes of Blu-ray players. And the transistors in various wireless infrastructure. In 2018 we started to see USB-C chargers with GaN hit the market. Since then many brands have released GaN chargers. With more on the way.

There isn’t an output advantage for GaN chargers. A 45W GaN charger charges as fast as a 45W silicon charger. And both heat up to similar temperatures. The difference is the GaN charger is smaller and lighter. While matching the silicon charger’s performance.

Costs continue to drop, but GaN is still more expensive than silicon. As such GaN chargers are usually priced at the high end of their peers. As with many things getting the smallest and lighter version costs a bit more.

Quick Charge 3.0 Over USB-C

The presence of Quick Charge over USB-C is against USB-C specifications. Such chargers have been around for years without issue. But that is not a guarantee of perfect compatibility for all devices.

Under section 4.8.2 of USB-C specifications, a proprietary charging method cannot change the voltage of USB-C output (between 4.40V and 5.25V) in a manner not defined by USB methods. Quick Charge operates at higher than default voltages and so goes against the specifications. USB Power Delivery is an open-source charging method. Created alongside USB-C, it is with specs even though it also increases the voltage. The big difference is USB PD uses communication lines to negotiate power transfer. Proprietary methods take over the data lines for their negotiation. They do so because legacy USB connections, such as USB-A, lack comm lines.

There is no known risk with running proprietary charging standards over USB-C. Manipulating the data lines does disrupt data transfers. But when plugging into a wall charger or power bank, there is no data transfer anyway. Some engineers warn against using any USB-C chargers supporting third party standards. The concern is unforeseen consequences, with future devices having compatibility issues.

I have not run into any issues with these fast charging standards on this or any other charger. It is a spec violation, and as such, you should be aware.


The CIO 100W USB-C GaN is about as fully featured of a charger as you’ll find.

  • 100W USB-C PD output, as high as USB PD spec allows
  • PPS
  • Quick Charge 3.0, Samsung AFC, Huawei FCP, Apple 2.4A
  • Dual USB-C PD
  • Dual USB-C PD and Quick Charge
  • Foldable prongs and a travel-friendly design

Fast charges iPhone 8/X/XR/XS/SE/11/12, Samsung Galaxy, and Google Pixel.

Fast charges LG, Motorola, and any other Android which supports Quick Charge. As well as supporting the old FCP standard for Huawei phones.

Nintendo Switch fast charges in handheld mode as fast as any other option. But the dock rejects it as a compatible charger. Probably just as well, as using the other USB ports would interrupt power to the system.

There is no USB-C charger feature missing from this model. It could have offered a more evenly split output between USB-C ports, going for 45W + 45W over its actual options. But the unbalanced output better supports one large device and one small device. That is what most, though not all, users need.

It is ideal as an all-in-one travel charger and would handle every one of my needs on the road except for powering a docked Nintendo Switch. In an office, especially those working with various devices, it’ll work as a laptop charger with the ability to adapt as needed.

If your needs only require USB-C PD for no more than two devices, there are smaller or cheaper options. But if you want 2-3 USB-C ports and enough power for your largest USB-C devices, look no further.

About CIO (Connect International One)

CIO is a smartphone accessories manufacturer out of Japan. Until recently they mostly operated in Japanese ecommerce sites, but have now come to North America via crowdfunding and Amazon. There is a 6 month warranty, bupport outside of Japan is limited. Expect to contact them through Amazon. You can see a translated version of their website here.

This particular charger started as a Kickstarter project, but is now available for retail sale.

Bottom Line

The CIO 100W USB-C GaN is one of the better examples of a true all-in-one USB-C charger. It supports maximum Power Delivery limits, the latest GaN and PPS tech, has many USB ports, and the ability to fast charge on up to three of them at once.

Buy if you:
  • Need to fast charge 2-3 various devices together regularly
  • Want a laptop charger capable of supporting many other devices, too
  • Are looking to simply your travel gear without giving up fast charging support
Don’t buy if you:
  • Want an even split of power between two USB-C ports
  • Only need up to two USB-C ports running Power Delivery

No products found.

[wpcd_coupon id=12311]

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