• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 34 subscribers
  • Views 110 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

SN65HVD06: output divider resistor suggession

Chi Zhang2
Intellectual 2690 points
Part Number: SN65HVD06

Tool/software:

Hi Expert，

my customer want to change these 2 resistor form 4K to 2K ohm, any risk? I didn’t see any limitation here, also we highlight matching impedance should be 60ohm, but it is not here, is it okay?

  • +1
    Guru 316640 points

    The SN65HVD06 itself has fail-safe receivers and does not need external fail-safe resistors, so any value is OK. These resistors are needed if there can be other receivers without failsafe on the bus, or if you want to increase the fail-safe noise margin.

    Termination resistors (of 120 Ω) must be placed only at the two ends of the RS-485 bus; I do not know whether this node is at one of the ends. The datasheet specifies a 60 Ω (±10 %) load as the parallel circuit of these two resistors.

  • 0
    TI__Genius 13402 points

    Hi Chi,

    I echo what Clemens has already pointed out.

    4K or 2K Ohms should not impact the performance. Ensure termination resistors are added to the system. This document covers it more in detail, but Clemens describes it well. 

    Best,

    Ethan