• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 49 subscribers
  • Views 221 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.

LPV511: High Side Current Sensing Implimentation

Vishal A1
Intellectual 540 points
Part Number: LPV511

Hi,

We have selected LPV511 OP-AMP for High Side Current Sensing . We require the following confirmation before proceeding,

1.Is the resistor R3 Internal/External to the IC? I assume as per the datasheet it is internal and has a fixed value of 10K which cannot be varied by the designer. Please confirm!

2.There is no need for a feedback resistor and we require only 3 resistors R1,R2 and R3 for proper current sensing as per the application circuit.

3. What is the min and max gain that we can configure with LPV511?

4.Can we configure gain for 1.366 when R3=10K and R2 = R1=7.32k and Gain of 50 when R3=10k and R1=R2=200E?

  • 0
    TI__Expert 6625 points

    Hi Vishal, 

    Please find my answers below:

    1. Resistor R3 is external to the IC. Please note that the "High side current sensing" circuit is just an example of an application for LPV511. So all the components around the op amp are external to the IC.

    2. Correct. You can read more about how this circuit works in the "Design Procedure" section of the datasheet.

    3. The gain of the circuit can be adjusted by the ratio of R3 to R1. But if you're referring to the gain of the op amp itself then that's dependent on the Aol curve. Aol is a parameter that's frequency dependent. 

    4. Correct (I'm assuming for the second part you meant R3 = 10k and R1=R2 = 200)

    Best Regards,

    Bala Ravi