How to connect a USB-C-based MacBook to a Thunderbolt display?

Solution 1:

As @Kevin McKenzie already said, and just to expand on it.

At present there is no adapter for the USB-C to Thunderbolt.

Here is quote from http://9to5mac.com/2015/03/09/apples-12-macbook-gets-new-usb-c-power-vga-usb-and-hdmi-adapters/

Thunderbolt Gen 1 and 2 don’t support USB 3.1, Type C or even 3.0 for that matter. An adapter wouldn’t have fixed this problem. However, Apple is releasing Thunderbolt 3 later in 2015. It’s not ready yet, because it’s developed with Intel and now Gen 3’s functionality is tied to Skylake chips – which will replace Broadwell shortly. I know. You’re thinking “But Broadwell just came out!” That’s true, but only because of delays. Now, you may wonder how a new MacBook without a Thunderbolt port or a Skylake chip will support a Thunderbolt Display.

Well, in short it won’t. That is unless Apple releases a firmware update for their Thunderbolt cables. Which they won’t. So it probably won’t support it. Considering the last time they updated it, I think we’ll see an update at WWDC, with a USB C port on the display itself.

Solution 2:

Right now, you don't. The Thunderbolt display requires a Thunderbolt connection as input, and while Apple did announce some USB-C dongles yesterday, none of them were USB-C to Thunderbolt. They may well come out with something in the future, or a third party may, or they may be releasing a replacement for the Thunderbolt display soon, one that also supports input via USB-C.

Solution 3:

If you go to the technicality the Thunderbolt Display, according to iFixit, is technically a DisplayPort monitor internally coupled to a Thunderbolt dock station with DisplayPort output, and the internal DisplayPort connection is actually detachable from the dock station assembly as a Mini DisplayPort cable (!)

So if you are brave enough to give the monitor a hack, with some quick drilling action on the chassis and a Mini DisplayPort extension cable you can actually detach the display from the internal docking station and use it as a standalone display and use the docking station portion of the machine independently. Ugly hack and probably not worth it since Apple already had a Mini DisplayPort+USB Cinema Display in the past.

Using one of that and a third party USB Type C to USB+Mini DisplayPort+Power adapter you can use that last generation Cinema Display on your MacBook actually.

Solution 4:

Apple have released a Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter.

https://www.apple.com/shop/product/MMEL2AM/A/thunderbolt-3-usb-c-to-thunderbolt-2-adapter

I have one of these. It works well, still providing access to the extra ports on the back of the Thunderbolt Display.

2 issues I have with the adapter: (1) it is quite long and slightly unpretty and (2) the Thunderbolt Display intermittently does wake from sleep, requiring that I unplug and replug the adapter.