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LMV841: Phase margin difference between rev.I and Rev.H

Ryuji
Guru 20090 points
Part Number: LMV841

Hello,

The LMV84x datasheet was revised at Oct/2017.
I have the question about this revision change.

(1) Phase Marin and Overshoot
In the EC table , the phase margin is not difference between Revision I and Revision H.Both specifications are 67 degree(typ).

However, typical characteristics is worse in Revision H from Revision I.
Could you please let me know this reason?
Is the phase margin specification in the EC table of Revision H correct?






(2) Overshoot measurement condition
Could you please let me know the measurement schematics and condition of Figure 29?
Regarding measurement condition, there is the measurement condition as f=250kHz, Av=+1 , Vin=200mVpp in the Revision H but there is no description in Revision I.

Best Regards,
Ryuji

  • 0
    Guru 20090 points
    Hello Team,

    I'm looking forward to your reply. I was requested these questions from the customer.

    Best Regards,
    Ryuji
  • 0 in reply to Ryuji
    TI__Expert 5830 points
    Hello Ryuji,

    I will look into this for you. This might take a couple of days to figure out.

    Best regards,

    Errol Leon
    Texas Instruments
    Precision Amplifier Applications Engineer
  • 0 in reply to Errol Leon6
    Guru 20090 points
    Hello Errol san,

    I appreciate your support.
    Are there any updated on this issue?

    Best Regards,
    Ryuji
  • 0 in reply to Ryuji
    TI__Expert 5830 points

    Hello Ryuji-san,

    I have looked into it. It looks some of the curves (such as: phase margin vs Cload) were retaken for a datasheet refresh. The devices used for the refresh measurements comes from a different lot than the previous data which is why you see a slight difference in phase margin. Still with this slight difference, the devices still falls within the standard distribution. Also, the curves from the refresh have higher resolution (more data points taken) than the previous curves.
     
    Best regards,

    Errol Leon
    Texas Instruments
    Precision Amplifier Applications Engineer

  • 0 in reply to Errol Leon6
    Guru 20090 points
    Hello Errol san,

    I appreciate your support.
    How about (2) question? I would like to know measurement schematics and condition.

    (2) Overshoot measurement condition
    Could you please let me know the measurement schematics and condition of Figure 29?
    Regarding measurement condition, there is the measurement condition as f=250kHz, Av=+1 , Vin=200mVpp in the Revision H but there is no description in Revision I.


    Best Reagrds,
    Ryuji