CAC-1332 HDMI to USB C 4K60Hz

Updated 3 days ago in USB Type C
4 on 28-12-2020

It uses USB power but does it transmit USB 2.0 data?

If it does do USB 2.0 data, then the description needs to include that information.

If it doesn’t do USB 2.0 data then I might as well just use a HDMI to DisplayPort adapter with a bi-directional USB-C to DisplayPort cable. Does it use the same converter as the CAC-1331?

The CAC-1331 mentions DisplayPort 1.2a support but the CAC-1332 doesn’t mention the DisplayPort version.

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3 on 28-12-2020

Hi Joevt,

The USB power does not transmit USB 2.0 data, it is only to power the adapter.

Not sure what solution you are looking for exactly but the 2 items you describe are completely different.

The CAC-1331 is HDMI to DisplayPort 1.2. The CAC-1332 is HDMI to USB-C, why would you want to know what DisplayPort version would be supported by an USB-C output? USB-C won’t fit into DisplayPort 😉 This is why it is not mentioned.

If you can describe to me what you are trying to achieve I might be able to help. Don’t forget to mention your hardware.

7 days ago

I suggest you read about USB-C and DisplayPort.

The signal at the USB-C connector of the CAC-1332 is DisplayPort. It is using the DisplayPort Alt Mode of USB-C. DisplayPort Alt Mode can include USB 2.0. USB 2.0 is used by USB-C displays like the LG UltraFine 4K to do audio, USB ports, and brightness control (all through USB devices). The LG UltraFine 4K requires four 4 of DisplayPort 1.2 to achieve 4K60. Some displays can do audio from the DisplayPort signal. And they can do brightness control using DDC/CI from the DisplayPort signal. I think the LG UltraFine 4K supports audio only from USB but can use DDC/CI to do brightness control (with third party app).

For USB-C DisplayPort Alt Mode, the number of lanes used for DisplayPort can be reduced from 4 lanes to 2 lanes so that the other 2 lanes can be used for sending and receiving USB 3.x. USB 2.0 uses different lines than DisplayPort and USB 3.x.

USB-C DisplayPort Alt Mode is used by USB-C docks and displays. Some docks allow 2 lanes of DisplayPort with USB 3.x, while some use 4 lanes of DisplayPort with USB 2.0. Some displays have an option or automatically switch between USB 2.0 or USB 3.x for the USB-C input (for example, if the display is using a different input, then it can use USB 3.x from USB-C).

The Apple USB-C Digital AV Multiport Adapter uses two lanes of DisplayPort 1.4 (and DSC). This allows the USB port to do USB 3.x.

5 days ago

I think I misunderstood you or misread your question.

I was replying to the CAC-1332’s micro USB power input :).

USB-C always has USB 2.0 data transfer, but on the CAC-1332 it has no function. And if the adapter supports 4K60Hz don’t you agree it needs all 4 lanes of the USB-C?


3 days ago

4K60Hz uses all 4 super speed lines of USB-C for DisplayPort 1.2 alt mode but USB-C also has separate high speed lines (D- and D+) for USB 2.0 that are always available for USB-C alt modes.

The CAC-1332 would be perfect if it included USB data (at least it would be much better – perfection is a moving target as new specs are introduced like HDMI 2.1). Some displays like the LG UltraFine 4K (which only have a USB-C input) use USB for audio instead of the audio from DisplayPort.

The female USB-C port is especially useful for USB-C devices/hubs/docks that have a non-detachable male USB-C connector. Of course, it would only work with those USB-C devices that don’t require USB 3.x and can accept four lanes of DisplayPort (many USB-C docks won’t work with four lanes of DisplayPort) unless the adapter can switch modes between two lanes of DisplayPort + USB 3.x and four lanes of DisplayPort + USB 2.0 like most USB-C host ports (like any Thunderbolt 3 port, or the USB-C port of some PCs and the MacBook and the Sunix UPD2018, and HP Thunderbolt Dock G2, etc.).

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