Can a USB-C with DP-altmode, output HDMI mode, like a native DP port can?

[Freesurfer]

Just about every displayport source with a physical DP port, can be passively converted with a dumb DP to HDMI adapter without any reframing. The displayport simply recognises this configuration and electrically outputs an HDMI signal, with the adapter just adapting the shape of the connector. I have done this a lot with an older laptop that only had a mini-DP output, and no HDMI.

But is this the same if the source is a USB-C port running in DP Alt mode? Can a USB-C port output HDMI electrically, with a passive adapter?
The reason I am asking is that I have 3m cable that is USB-C male in one end (laptop end), and a full size displayport male plug in the other end (monitor end) which works well with displayport monitors. But sometimes I need to be able to connect the laptop to a TV or old monitor. So I thought of just getting a dumb adapter dongle with a DP female port, to HDMI male, to do the same kind of conversion. (I travel a lot, with weight at a premium, can't lug too many cables).

However to my surprise, such an adapter does not seem to exist anywhere. I do see the reverse gender of the same thing, or female HDMI to female DP which are not bidirectional which could "fit" with a normal HDMI cable added in between, but cannot pass the signal that direction.
This makes me wonder if there is a reason these adapters don't exist. Because because that conversion isn't possible. Does anyone know?

AI only gives "It could maybe work, but it could also maybe not work, who knows?" kinds of answers.

[wraper]

Just about every displayport source with a physical DP port, can be passively converted with a dumb DP to HDMI adapter without any reframing. The displayport simply recognises this configuration and electrically outputs an HDMI signal, with the adapter just adapting the shape of the connector.]

Wrong. While "passive" DP++ to HDMI adapters are dumb, they actually contain a level shifter IC because DP and HDMI are not electrically compatible.

Can a USB-C port output HDMI electrically, with a passive adapter?

No, but active adapters and cables are cheap.

[langwadt]

Just about every displayport source with a physical DP port, can be passively converted with a dumb DP to HDMI adapter without any reframing. The displayport simply recognises this configuration and electrically outputs an HDMI signal, with the adapter just adapting the shape of the connector.]

Wrong. While "passive" DP++ to HDMI adapters are dumb, they actually contain a level shifter IC because DP and HDMI are not electrically compatible.

the adapter is just a cable no level shifters or anything, dp++ can send dp or hmdi

[wraper]

Just about every displayport source with a physical DP port, can be passively converted with a dumb DP to HDMI adapter without any reframing. The displayport simply recognises this configuration and electrically outputs an HDMI signal, with the adapter just adapting the shape of the connector.]

Wrong. While "passive" DP++ to HDMI adapters are dumb, they actually contain a level shifter IC because DP and HDMI are not electrically compatible.

the adapter is just a cable no level shifters or anything, dp++ can send dp or hmdi

I suggest you researching the topic before refuting actual correct information with uninformed BS. https://www.mouser.com/datasheet/3/1014/1/MAX9406.pdf

[Phil1977]

Hardware DP ports have DP and HDMI-Mode. Passive DP to HDMI adapters trigger the HDMI-Mode and no further level shifting is necessary.

USB-C ports theoretically have a HDMI-Mode, but it´s rarely used. Practically you always need an active level shifter if you connect USB-C to HDMI.

[wraper]

Hardware DP ports have DP and HDMI-Mode. Passive DP to HDMI adapters trigger the HDMI-Mode and no further level shifting is necessary.

Yet another one. DP++ outputs HDMI signal. But voltage is wrong, including DDC voltage, PWR is 3.3V instead of 5V too. And DP is AC coupled unlike DC coupled HDMI.

[Phil1977]

Sorry you´re right, passive adapter contain level shifters.

Anyhow, the consequences for the user are as described before: DP++ enables HDMI mode, which allows the usage of so called "passive" adapters which contain level shifting, but no further intelligence.

USB-C Alt Mode DP has no such mode, so that so called "active" adapters are required - which are real protocol converters.