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.

LF353: How are Specifications for Open Loop Gain Determined?

Part Number: LF353

The LF353 data sheet shows typical/min values of OL gain of 100/25 V/mV and worst case (over temp) as 15 V/mV.  My assumption is that you arrive at these values through some combination of analysis and testing, but would like to know what the rationale is for these specs.  This question is not really specific to the LF353.  I'm just trying to council my students to abide by your worst case product specifications, but would like information from you to substantiate my claims.  

Thanks!

  • Hi Spitzer,

    there are several methodes to measure the open loop gain. One is shown below:

    Kai

  • Hello,

    When designing a new product we determine the typical and/or min/max specifications through thorough testing (often called characterization) of the device. We then analyze the data to determine the limits of the device.

     While we don't use simulation to determine the specifications provided in our datasheets, we do use simulation as a tool to correlate our measurements with.

     You can find more information on the qualification of our devices by going to our Quality and Reliability webpage.

    Thank you,

    Tim Claycomb

  • Kai,

    Thanks very much for the quick response, and also for a terrific new lab exercise!

    The students are now exploring CL gain errors due to finite loop gain.  They have already completed a paper assignment that involves analysis of CL gain errors based upon worst case OL gain specifications obtained from the LF353 data sheet. 

    I had already planned to assign a lab exercise involving measurement of gain error for a high gain (1000) amplifier.  I can have them use this procedure to measure OL gain and use it to quantify the previously measured CL errors.

    Much appreciated!

    Jeff

  • Tim,
    Thanks for the clarification; I'll be sure to share this with the students.
    Jeff