• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 47 subscribers
  • Views 586 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.

LM2902: Item of function test

Shinichi Inoue
Guru 21701 points
Part Number: LM2902

Dear Specialists,

My customer is considering LM2902 and has questions about device function test.

I would be grateful if you could advise.

---

We'd like to conduct a kind of stress test (thermal, shock and etc) and confirm deterioration of the device.

And then we perform a simple test of the device before and after the examination and confirm the difference.

I picked up specific items.
Are these items sufficient?

· Current consumption
· Input offset voltage
･Supply Voltage Rejection Ratio
･Input Bias Current
･Input Offset Current
･Voltage Gain
･Common Mode Rejection Ratio
·Output Voltage H level and Output Voltage L Level

Could you please provide the test circuit your recommend.

---

I appreciate your great help in advance.

Best regards,

Shinichi

  • 0
    TI__Guru**** 165146 points

    Hello Shinichi-san,

    Some of this will be difficult and time consuming to do on a lab bench. Some tests below are close to data sheet conditions but not exact.

    · Input offset voltage
    ･Supply Voltage Rejection Ratio
    ･Voltage Gain
    ･Common Mode Rejection Ratio

    All the tests above use Vio at one or two device operating points.

    Top left schematic is measure Vio when VOUT = VCM.  Top right when VOUT not same as VCM
    Bottom row is simplified servo loops. Actual circuits are more complex.

    · Current consumption

    Measure ICC in unity gain, set Vin to 1V or similar.

    ･Input Bias Current
    ･Input Offset Current

    Measure input current with one input a 0V and the other at 10mV  

    ·Output Voltage H level and Output Voltage L Level

    Apply at least 1V input difference, add load to output 2k or 10k to ground.

  • 0 in reply to Ron Michallick
    Guru 21701 points
    Hi Ron,

    Thank you for your reply.

    I'll discuss these information with the customer.

    If he has an additional question, I consult you again.

    I appreciate your great help.

    Best regards,
    Shinichi