SN65C1168E-SEP: SN65C1168E-SEP's dumping resistor

Takeshi Tachibana

Prodigy 30 points

Part Number: SN65C1168E-SEP

Is there a recommended value for input/output dumping resistor that is required for SN65C1168E-SEP?

5 months ago

0 Ethan Sempsrott 5 months ago

TI__Mastermind 27342 points

Hi Takeshi,

I am not familiar with the term "dumping" resistor. Are you referring to the termination resistor which goes on the differential bus pins?

Best,

Ethan

0 Takeshi Tachibana 5 months ago in reply to Ethan Sempsrott

Prodigy 30 points

I am sorry. "Termination resistor" is correct.

0 Clemens Ladisch 5 months ago in reply to Takeshi Tachibana

Guru 325160 points

The termination resistor should match the characteristic impedance of the cable. For RS-422, this is typically 100 Ω; for RS-485, 120 Ω. (Note that RS-422 uses unidirectional signals and requires only a single termination resistor at the receiver; RS-485 requires exactly two resistors, one at each end of the bus.)

0 Ethan Sempsrott 5 months ago in reply to Takeshi Tachibana

TI__Mastermind 27342 points

Hi Takeshi,

What Clemens said is accurate. If you need more information, please reference this specific termination guide:

https://www.ti.com/document-viewer/lit/html/SSZTB23

Or use our general RS-485/RS-422 guide which has a section on termination:

https://www.ti.com/lit/an/slla070d/slla070d.pdf

Best,

Ethan

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SN65C1168E-SEP: SN65C1168E-SEP's dumping resistor