• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 48 subscribers
  • Views 348 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.

Current Sense Amplifier-Sense Resistor Layout

Hari T O0
Genius 3820 points

Hi Team,

In finished current sense amplifier video lecture series .

Regarding sense resistor layout they said that the tracks going from sense resistor to current sense amplifier should be length matched.

May i know why is it so,if it is not length matched may I know what are the consequences .How it will affect the measurements.

Regards

Hari

  • 0
    TI__Mastermind 27410 points

    Hi Hari,

    The main idea is to keep impedance matched so that we don’t create a systematic error. The error equals to the bias current times the mismatch resistance. And it appears as an offset.

    Even if the tracks are not identical, in most cases of high or low side current sensing, the error is so small that it doesn’t hurt. It is something that usually can be easily avoided however, by more or less matching the two tracks.

    In practice you’ll find that the tracks are almost always naturally matched once you start placement and routing.

    Regard, Guang