• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 47 subscribers
  • Views 303 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.

Original question:

LMP2012QML-SP: LMP2012QML-SP

LMP2012QML-SP: LMP2012QML-SP

user5940158
Intellectual 660 points
Part Number: LMP2012QML-SP
Other Parts Discussed in Thread: LMP2012QML

I am using LMP2012QML (5962L0620602VZA) op amp on a space flight board. The output was inadvertently shorted to ground. I'm wondering if this op amp has output current protection or if the part has been stressed and I would need to replace it.what can I do?
Thanks.

  • 0
    TI__Guru* 77521 points

    Hi 

    Here is my questions. 

    1. What are supply rail voltages?

    2. What is output voltage for the application?

    3. Are there output current limiting resistor in the design?

    4. How long was the short?

    Below is the absolute max. ratings in this part. If the Vout current exceed 30mA. the part may get damaged.      

    If the short scenario exceeds the max. output current ratings, then it is recommended to replace the part in a critical application, even if it is not damaged. This should be part of the risk management. 

    Best,

    Raymond

  • 0 in reply to Raymond Zhang1
    Intellectual 660 points

    Here's my answers:
    1. We are operating this parts with 0,+5V rails.
    2. Nominal output voltage is 0.5V, however, the voltage at the output during the short was about 20mV.
    3. I do not have any output current limiting resistors in the design.
    4. The short was probably about 1 minute.

    Yeah I saw in the datasheet the max output current is 30mA. I don't know what the output current was during the short but it seems that it likely exceeded the max 30mA. Therefor, I assume the part has been stressed and will need to be replaced. Do you have any recommended replacement parts？
    Thanks

  • 0 in reply to user5940158
    TI__Guru* 77521 points

    Hi ,

    I did the short circuit simulation, verify it with the datasheet and our application engineers. Here is what we concluded -->  The part does NOT need to be replaced --> LMP2012QML was pushed into Automatic short-circuit protection mode. 

    The simulation is correct and it shows a short-circuit current of 16mA ( datasheet shows 15 mA) . The IC increased approx. (5-0)*16.21mA*175C/W = 14.1 C above the ambient temperature when the short was occurred. The IC's power dissipation is approx. 81mW; the max. power dissipation is rated at 714mW according to the datasheet. 

    The absolute max rated current of 30 mA applies when the output is driven directly by Short to battery/Power Source or inductive kick-back. The scenario did not occur in your description of the shorted circuit event. 

    Enclosed in the Tina simulation:

    /cfs-file/__key/communityserver-discussions-components-files/14/LMP2012QML_2D00_SP-08282020.TSC

    If you have additional questions, please let us know. 

    Best,

    Raymond