• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 47 subscribers
  • Views 338 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.

INA780A: Effect of Internal Kelvin Resistance on System Gain Error

Maki Shota
Prodigy 10 points
Part Number: INA780A


Tool/software:

Hi Team

5.5 Electrical Characteristics

System current sense gain error is 1.25%, but there is a difference of 350-500uΩ in Internal kelvin resistance. If the IC is used without compensation, is the gain error due to Internal
resistance dominant?Do you have manufacturing scatter data for this resistance?

  • +1
    TI__Mastermind 32395 points

    Welcomed Appreciated Engineer,

    You are correct. There is a temperature dependent compensation inside the device that essentially calibrates out this tolerance and temperature coefficient of internal Kelvin resistance. If this compensation we’re not there, gain error would be dominated by variance of Kelvin resistance.

    Our manufacturing data is reflected in the maximum and minimum limit specifications of Kelvin and Package resistance. I’m not exactly sure what you mean by scatter data, while distributions can be considered as Gaussian, the most robust practice is to assume internal resistances could reach worst-case maximum value.

    Sincerely,

    Peter