How to Connect Your USB-C Mac to Older Peripherals

Introduce your peripherals to Thunderbolt 3 (USB-C)

Apple first introduced the USB-C port in the 12-inch MacBook in 2015. A year later, the Thunderbolt 3 (USB-C) port appeared in the 2016 MacBook Pros. It has the same size and shape as the familiar USB-C port, and it supports USB-C devices, among others.

The 12-inch MacBook had one USB 3.1 Gen 1 port, which is used for charging, video out, and USB 3 data. While the use of the USB-C port in 2015 was innovative, it's the Thunderbolt 3 (USB-C) port on the 2016 MacBook Pro and subsequent Macs that became the standard.

USB-C (Type-C) port
Maurizio Pesce / Wikimedia Common / CC BY 2.0

Thunderbolt 3 (USB-C)

In addition to accommodating USB-C peripherals, Thunderbolt 3 supports USB 3.1 Gen 2, DisplayPort, HDMI, and VGA through the same port via adapters. You can say this is the one port to rule them all, and it means an end to the collection of ports on the Mac.

Mac Models With Thunderbolt 3 (USB-C) Ports

  • Mac Pro (2019)
  • Mac mini (2018)
  • iMac Pro (all models)
  • iMac (2017 and later)
  • MacBook Air (2018 and later)
  • MacBook Pro (2016 and later)

Most people who already have a collection of peripherals, including printers, scanners, cameras, external drives, displays, iPhones, and iPads, are going to need an adapter to make the connection to the Thunderbolt 3 (USB-C) ports.

Thunderbolt 3 Accessories

Peripheral manufacturers are hard at work creating new versions of their products with Thunderbolt 3 ports. That will make connecting your compatible Mac to these devices an easy prospect, with only one type of cable and no adapters needed. Monitors, external enclosures, docking stations, and many more peripherals are already available with Thunderbolt 3. Printer and scanner manufacturers are jumping on the bandwagon, along with camera makers and others.

Until then, you need to know how to connect your Mac to older peripherals.

Connect USB 2 and USB 1.1 to Thunderbolt 3 (USB-C)

USB-C peripherals can plug directly into the Mac Thunderbird port. Connecting older peripherals with earlier versions of USB requires an adapter that converts the USB 2 or USB 1.1 to USB-C. A USB-C to USB adapter, like the one available from Apple, has a USB-C connector on one end and a USB Type-A connector on the other.

Although USB Type-A is the most common form for this adapter, there are smatterings of adapters that forgo the standard Type-A connector for the USB Type-B or micro-USB connector.

You can use this type of adapter to connect flash drives, cameras, printers, or other standard USB devices to your Mac. You can even use this adapter to connect to your iPhone or iPad, although recent models require a Lightning to USB adapter.

One note about these adapters: the speed is limited to 5 Gbps. If you want to connect a USB 3.1 Gen 2 device that can support 10 Gbps, you need to use a Thunderbolt 3 to Thunderbolt 3 adapter.

Connect HDMI to Thunderbolt 3

Apple's USB-C Digital AV Multiport Adapter is ideal for connecting your Mac to the HDMI (USB-C) input of a display or TV. This type of adapter is for basic HDMI supporting a 1080p signal at 60 Hz or a UHD (3840 x 2160) at 30 Hz. If you're looking for an adapter to handle a 4K or 5K display at 60 Hz, you need an adapter that supports DisplayPort connectivity. This connector requires macOS Mojave (10.14.6) or later.

Connect VGA to Thunderbolt 3

To mirror your display to a VGA-enabled TV or display, you need a USB-C VGA Multiport Adapter. These adaptors tend to be limited to 1080p. Once again, for a higher resolution, look to the DisplayPort adapters.

Connect DisplayPort to Thunderbolt 3

The Moshi USB-C to DisplayPort Cable is what you're looking for if you need DisplayPort connectivity. This cable can support 5K video at 60 Hz with multichannel digital surround sound.

Connect Lightning to Thunderbolt 3

A Thunderbolt 3 to USB adapter can work with the Lightning to USB adapter you may already have for your iPhone, but you may consider it awkward to use two adapters to make a single connection. The fewer connectors and adapters in line, the less chance there is for failure. There's a USB-C to Lightning cable you can use available from Apple and a few third parties.

Connect Thunderbolt 2 to Thunderbolt 3

If you already have Thunderbolt 2 device, the Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter is what you need.

This Apple adapter also works for connecting older Thunderbolt 2 Macs to Thunderbolt 3 peripherals, but before you say yippee and run out to buy an adapter and a newfangled Thunderbolt 3 device, make sure the Thunderbolt 3 peripheral works with a Thunderbolt 2 Mac.

The Thunderbolt 3 specification says it's backward compatible with the older Thunderbolt 2, but more than one manufacturer asserts its Thunderbolt 3 peripherals are not compatible with Thunderbolt 2.

Connect Firewire to Thunderbolt 3

If you need to connect a FireWire device to a Mac using the Thunderbolt 3 port, then you're probably in the market for an Apple Thunderbolt to FireWire adapter. It connects to the Mac and gives you a FireWire 800 port with 7 watts to run bus-powered peripherals. This adapter requires OS X 10.8.4 or later.

When you're shopping for a Firewire adapter, be sure you're getting the right adapter (Thunderbolt 3 in this case), because previous generations of adapters are not the same.

Thunderbolt 3 to Thunderbolt 3

A Thunderbolt 3 (USB-C) Cable connects a Mac with Thunderbolt 3 to any other Thunderbolt 3 device. It can also be used for daisy-chaining one Thunderbolt 3 peripheral to another.

Don't be fooled by cables that have a USB-C connector at each end; this alone doesn't signify the cable is a Thunderbolt 3 cable. You can tell the two types of similar-looking cables apart by examining the USB-C connector; you should see a single lightning bolt logo on Thunderbolt cables.

Thunderbolt 3 Is Here to Stay

Thunderbolt 3 (USB-C) is fast, versatile, and well on its way to being a universal connection for most things you can attach to a computer. Apple has ripped out legacy ports and replaced them with Thunderbolt 3. The only non-Thunderbolt port left the headphone jack, and even that is destined go away someday, replaced entirely by wireless connections or third-party Thunderbolt docking stations with headphone and microphone inputs.