SN65HVD1781: propagation delay, rise time and fall time vs temperature

Naveen Bevara

Intellectual 1970 points

Part Number: SN65HVD1781

Hi Team,

Do we have propagation delay, rise time and fall time vs temperature variation graph for SN65HVD1781DR?

over 5 years ago

0 Hao L over 5 years ago

TI__Mastermind 25705 points

Naveen,

Are you looking for the driver's characterization data, like tr, tf, tPHL, tPLH? I can generate the plots based on some bench data.

Regards,

Hao

0 Prachi Moghe over 5 years ago in reply to Hao L

Prodigy 110 points

Hi,

Yes please. Driver's characterization data would be helpful.

Thanks,

Prachi

0 Hao L over 5 years ago in reply to Prachi Moghe

TI__Mastermind 25705 points

Prachi,

Here are the plots.

1) rise/fall time with Vcc and temperature variation

2) delay time with Vcc and temperature variation

Regards,

Hao

0 Prachi Moghe over 5 years ago in reply to Hao L

Prodigy 110 points

Hi,

Looking at the plots, we consider that for Vcc 5V, rise/ fall time varies between 210us and 230us over temperature range -40degC to 85degC. Similarly, propagation delay varies between 125us to 130us over the temperature range.

Thanks Hao and Naveen!

Regards,

Prachi

0 Prachi Moghe over 5 years ago in reply to Hao L

Prodigy 110 points

Hi,

I think I misread the timing parameters in microsecond. So, please confirm once the units for rise/ fall time and delay time, whether it is in nanoseconds or in microseconds.

Thanks,

Prachi

0 Hao L over 5 years ago in reply to Prachi Moghe

TI__Mastermind 25705 points

Prachi,

Yes, the unit is nanoseconds. The data are within the specification of the datasheet. Please let me know if you have more questions.

Regards,

Hao

0 Prachi Moghe over 5 years ago in reply to Hao L

Prodigy 110 points

Hao,

Thanks for the confirmation. I understood.

As I am new to this domain, I would like to understand relation between data rate and frequency of operation as well. The maximum signalling rate is 1Mbps as per datasheet. Will this IC operate at 1.2kHz frequency ?

Also is it possible for you to share PSpice simulation model for this IC?

Thanks,

Prachi

0 Hao L over 5 years ago in reply to Prachi Moghe

TI__Mastermind 25705 points

Prachi,

Yes, the device can work with any data rate lower than the maximum specification on the datasheet. However it's not recommended to use high data rate devices in low data rate applications, because the fast edges might cause some potential EMC issues.

For new TI RS-485 parts, please check out this post.

https://e2e.ti.com/support/interface/f/138/t/849650

Due to the electrical characteristics, the transceivers usually come with an IBIS model, which describes the IO behavior. Here are the models for 5V operation and 3.3V.

https://www.ti.com/lit/zip/sllc349

www.ti.com/.../sllc350

Regards,

Hao

Interface

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SN65HVD1781: propagation delay, rise time and fall time vs temperature