SN65LVDS387: Series connection from SN74LVTH16245ADGGR support with signal sharing

Nanjunda M

Part Number: SN65LVDS387

Hi,

I have a requirement wherein I have one single-ended signal that is to be split into 100 LVDS signals.

So I have given this single ended signal to SN74LVTH16245ADGGR single ended buffer.

At the input of this buffer, there is an LVDS receiver SN65LVDS390D. This single-ended signal is connected to 6pins of the single ended buffer SN74LVTH16245ADGGR

At the single ended buffer output, the signals are driven from 6 outputs and connected to 16pins of the one LVDS driver SN65LVDS387DGG.

With this system present, I'm not sure whether this splitting of signals will workout.

Can you please help me. Is there anything wrong with this implementation? Do I need to modify anything in this?

Below is the simple diagram for understanding.

Please help ASAP.

Thanks & Regards,

Nanjuda M

over 6 years ago

0 Jorge Llamas (SWAT) over 6 years ago

TI__Expert 7395 points

Hello,

Thank you for your interest in our products.
I have assigned a support engineer, so you should be getting a response soon.

Regards,
Jorge

0 Yaser Ibrahim over 6 years ago in reply to Jorge Llamas (SWAT)

TI__Genius 10250 points

Hi Manjuda,

I don't see any issues with this in principle, as long as your signalling rate can be handled by SN74LVTH16245ADGGR (rise time is 3.7 ns). How fast is your signal?

Regards,
Yaser

0 Nanjunda M over 6 years ago in reply to Yaser Ibrahim

Expert 2485 points

Hi Yaser,

The individual line is expected to support data-rate of 20MBPS.

Thanks & Regards,

Nanjunda M

0 Yaser Ibrahim over 6 years ago in reply to Nanjunda M

TI__Genius 10250 points

Hi Manjuda,

20Mbps should be no problem.

Regards,
Yaser

0 Nanjunda M over 6 years ago in reply to Yaser Ibrahim

Expert 2485 points

HI Yaser,

What would be the maximum data-rate supported by this setup ?

How do I calculate the same?

Thanks & Regards,
Nanjunda M

0 Yaser Ibrahim over 6 years ago in reply to Nanjunda M

TI__Genius 10250 points

Hi Nanjunda,

Max supported rate generally depends on max rise/fall times. SN74LVTH16245ADGGR has the longest rise time (3.7 ns), so the max switching rate it supports is roughly 1/(3*tr), which yields a rate of about 90 Mbps.

0 Nanjunda M over 6 years ago in reply to Yaser Ibrahim

Expert 2485 points

Hi Yaser,

Thanks for the above inputs, I have one more concern in the same above setup is, whether a single output from SN65LVDS390D can drive the 6 inputs of the SN74LVTH16245ADGGR?
Have anyone tried this?

Thanks & Regards,
Nanjunda M

0 Yaser Ibrahim over 6 years ago in reply to Nanjunda M

TI__Genius 10250 points

Hi Nanjunda,

I don't know if anyone tried this. However, the max input current of SN74LVTH16245ADGGR is only 5 uA (to A/B inputs), and the output of SN65LVDS390D can supply this x 6 without a problem (please see Figure 5 in the datasheet).

Regards,
Yaser

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SN65LVDS387: Series connection from SN74LVTH16245ADGGR support with signal sharing