Creating a PCB with HDMI Connectors for Black Screen Effect: Which Pins to Break?

Question

Hello! Below is a list of HDMI connectors. Generally, I would like to make a printed circuit board on which there would be two HDMI connectors (pin in pin), and thanks to which after giving the appropriate control signal I would get the black screen effect. The question is, which pins would I...

A.Gieronimo · Accepted Answer

5V can be used by input circuits but it doesn't have to be in inches, so the effect will depend on the equipment.
The surest effect will be to cut the TMDS Clock.
Someone will write that hotplug, but it is just as sure as 5V, one manufacturer will use and another oil.

djlukas · Answer

To detect the connector, use pin 19 Hot plug detect.

Pawel_1985 · Answer

Thanks for the answers.

And I have a question, can I use these 5 V to power electronics? Of course, the power consumption of this line would be in the order of a few miles amperes.

And the TMDS Clock signal (two lines + and -), how do you best disconnect? Which solution would be the best: a transistor, a bistable relay or a multiplexer?

A.Gieronimo · Answer

A multiplexer, unless you mean a buffer rather, would be the safest. This 5V output has a maximum load of 50mA and it is not known how much the receiver will take. Generally, you can use.

Artek_łódź · Answer

I am sorry for connecting to the subject but I have a similar question with the fact that from the HDMI socket I would like to take some power to power one or two fans to cool the TV case. It's quite old and there is no USB in it, so can I make a cable with a plug and only two cables connected (17,18). Will this solution work and is it safe? The fans are on 12V DC but it suits me that it would work on 5V (i.e. half slower). They charge a maximum of 0.12A each.
Thank you for your answer.

zster · Answer

Have you read the whole topic? It clearly says that the power supply in HDMI has a capacity of 50mA max and you want to connect two 120mA fans, i.e. 240mA in total ...

Artek_łódź · Answer

Now I see. Somehow I miss this post Sorry and thanks!

zster · Answer

It happens

The only solution is to find a 5V or 12V power supply inside the TV and connect the fans there. Or an external power supply and a small relay or circuit with MOSFET transistor (so-called logic level MOSFET) connected from the HDMI connector - this way the fans will start only when the TV is on.

Artek_łódź · Answer

Very cool ideas!
It would be ideal to power them from the inside of the TV, but I honestly do not know where to connect it securely. TV to Funai LC5-D32BB / 1. So far I have connected a 5V, 0.5A power supply and they work super quietly and at the same time efficiently. I have a TV connected so that they turn on and off the same way. I drilled holes in the casing and screwed the fans together with the protective grilles. One cools the transformer, rectifier diodes and 2SK3799 hot transistor on the inverter board, while the other cools the power supply itself. The effect is really great.

Pawel_1985 · Answer

The subject is old, but it's back in favor, I'm preparing a plate and I would like to make sure that the buffers selected are adequate. The search criteria are a non-inverting, three-state buffer (one with an additional foot, setting the output to a high impedance state). The choice fell on such systems: 74AHC2G125.74LVC1G125GV.125 Another issue is the frequency of these systems. How often does the TDMS line work so as to select the best buffer in terms of propagation times of signal switching. I would like to connect both TMDS Clock signals via buffers.

Creating a PCB with HDMI Connectors for Black Screen Effect: Which Pins to Break?

Post #1

Post #2

Post #3

Post #4

Post #5

Post #6

Post #7

Post #8

Post #9

Post #10

Post #11

Topic summary