NE5532: NE5532ADR

Hello, 

We do not have a specification for THD for the NE555 in the product datasheet. I have written a detailed application note "How to Measure Total Harmonic Distortion of an Op-Amp and THD + N Fundamentals" that can be found here:

How to Measure Total Harmonic Distortion of an Op-Amp and THD + N Fundamentals

For the app note I used the AP555 which is the standard equipment for measuring THD in the industry. It is important to note that we use a special test circuit when measuring THD and I cover this circuit in the application note. The increase in distortion you are observing is classic behavior of any op amp as it loses Aol vs Frequency. If you run the THD out further to let's say 80kHz I suspect the other units will also increase at some point for the same reason. 

If you are seeing a difference in devices that are both NE5532 than it may be related to the FAB change that is outlined in the PCN that was sent out November 15, 2023. 

https://www.mouser.com/PCN/Texas_Instruments_PCN20231114004_20231115101151195.pdf

Best Regards,

Chris Featherstone

Dear Chris,

Thank you for your prompt and helpful advice.

Please be so kind and comment on the following message from our customer:

Please confirm whether the presented distortion graph (THD+N) corresponds to the typical behaviour of the NE5532ADR circuit and should be considered within the design characteristics, even though this parameter is not formally specified in the data sheet.
In light of the above, should this observation be treated as normal behaviour in accordance with the design or as a circuit malfunction?