• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 34 subscribers
  • Views 593 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

Parallel 5VOP of SN65HVS880/881/882

James Liang
Prodigy 70 points
Other Parts Discussed in Thread: SN65HVS880

Cascading several SN65HVS88x will definitely handle more digital inputs. Then 5VOP of each 88x will be parallel to each other (Most parallel linear regulators do not work well because the multiple feedback loops try to control same voltage point). Assume there are some other 5V peripheral ICs, I am wondering whether we could use those 5VOP to supply the multiple external 5V peripheral ICs for stability, load capacitance and load current issues.

 

  • 0
    TI__Mastermind 28265 points

    Paralleling multiple 5V outputs should cause no stability issues when you follow the stability recommendations for the output capacitors of the linear regulator in the SN65HVS880 data sheet on page 12.

    Regards, Thomas

  • 0 in reply to Thomas Kugelstadt
    Intellectual 350 points

    Does it mean that I can tie all 5VOPs from SN65HVS880 to increase load current?

    I will cascade total four SN65HVS880s 

    I'm not sure whether I can tie output pins togehter.

  • 0 in reply to Hak-Jin Jeong
    TI__Guru 62910 points

    Hi Hak-Jin,

    I don't recommend shorting together multiple 5-V outputs in order to increase the load current above what a single device is capable of.  With this kind of set-up, there is not a good way to ensure that current is provided equally from all the supplies.  Depending on the load current required, this could result in some regulators providing more than their specified limit.

    For cases where the regulator output can be higher than the supply voltage needed, sometimes ballast resistors can be used to help with this load balancing.  Here is an application note on that topic: http://www.ti.com/lit/an/slva250/slva250.pdf.

    Regards,
    Max