TSER953: V3link transmission frequency

Hello,

I am not sure I understand the question?  Are you asking because you are looking for what cable to use?  If so we provide a channel spec and it should be possible to determine something that could work for you with that.

Regards,

Nick

No not such thing as cable, it's more about the connection at the end  of the cable. But nevetheless: A recommendation regarding STP cable (CAT-category) would be helpful.

The point is that the application is in a residential area where no cable including RJ45-connectors is being used but instead cable where the connection to a sort of receptacle (whatever receptable - that's subject to investigation) is being established on site (the cable is getting through wall inlets, on top of which an applicance is mounted after the cable is wired into a sort of wire receptacle.

Therefore it is very important to know more about the transmission bandwidth over the cable. As usual, with advanced modulation techniques it can be lower than the bit rate...

I hope that the question is clarified a bit.

FYI: In the case that the bandwidth cannot be handled reliably through a v3link, the customer must consider another bom-cost figure for remote camera units including an MCU that provides a compressed videostream over conventional ethernet, instead of uncompressed.

Hello Rob,

I am looking into this.  Allow me a few days to see if we have a recommendation.  We are currently working on putting together some material for this.

Regards,

Nick

Nicholas, could you provide an (updated) information regarding the time still needed to prepare a recommendation?

Hi Rob,

Sorry for the delay here.  We cannot take on the task of validating specific cables that can work or not.  We can provide a channel spec that defines the channel and a cable can be selected around those requirements.  With that said something like CAT6 can work but would need to be verified with the cable vendor.

Regards,

Nick

That's all okay, what you say!

But it is also true that transmission bandwidth is a very necessary spec issue that is needed to clarify the cable stuff (where the eval boards only provide coax), as well as being able to evaluate the connection from cable to board (connector).

Regards,

Rob

Hi Rob,

What information exactly do you need from our side then?  The FPD-Link channel typically operates at 4Gbps and the cable would need to support that.

Regards,

Nick

I'm sorry, Nicholas, to get into a bit of repeat mode. It's the transmission bandwidth which must be specified. Or, in a former entry in this thread: The transmission frequency. Since such is a hard fact, it shoudn't be so difficult to specify that. Remind please that the transmission bandwidth in different ethernet classes is lower than the bps-spec.

This information is very, very essential to being able to make a well-funded recommendation whether a certain cabling + connection (through a wall inlet) should work with v3link or not. The fact that TI only provides eval kits based on Coax connection makes me skeptical. It's up to you now.

Hi Rob,

Is the information you are looking for located in section 8.1of the 953 datasheet?

Regards,

Nick

Well, the datasheet says 20 MHz to 2.1 GHz ("up to 4.16 Gbps"). That's a bit vague, and in worst case: even slightly beyond the CAT8 standard. From this point of view I understand quite well your earlier remark of "currently working on putting together some material for this". Also because of absence of STP-based evaluation hardware.

Am I right in the assumption that 4.16 GHz is probably not recommended at all in the scope of current STP-cable classes? But even for the case that CAT8 fits the scheme, what about the 50 Ohms impedance requirement? The datasheet only classifies suggested characteristics for 50 Ohms cabling.

Perhaps, the intended application can operate below 4.16 Gbps, because the bandwidth requirement of the Back Channel (for GPIO-based auxiliary transmission to the camera unit) can be reduced, just because of some design changes that have been prepared to allow this. But for being able to evaluate this, a more precise bandwidth spec vs bit rate is necessary - also with total cost (including cable & connector) in mind.

Meanwhile a consultation with the customer has been carried out. They decided to follow my advice to not take the risks associated with v3link in their application environment. As a consequence, the v3link is dropped from the technical concept.