Even LM741 are faked

[dbanner]

Take a look at this short video https://www.youtube.com/watch?v=gueH...cmUgZmFrZWQ%3D

[Carl-NC]

I assumed the other fake opamps were 741s. That's crazy to fake such a cheap opamp.

[Jose]

I bought CD4538 ICs for a Delta Pulse I was building, the pulse times were less than 50% of normal values. I think they are fake, or they have different characteristics to the ones I used before, I don't know.

[MOR_AL]

Hello.
I had problems with fake operational amplifiers.
I decided to create a test circuit for the operational amplifiers I have.
The circuit worked well. I had the opportunity to check which operational amplifiers were fake and which were not.
In addition, the circuit allows me to identify the quality of the fake operational amplifiers. Some of them can still be used with restrictions and others went straight to the trash.
I made two videos on YouTube showing the project and the tests performed.
If you are interested, I added both links.
The videos are in Brazilian Portuguese, but the language can be edited and the description of what is being said is written in English.
Access the settings > Subtitles/CC and convert the text to English.
First video:
https://www.youtube.com/watch?v=1rorBNa5q1g

Second video:
https://www.youtube.com/watch?v=vzWiiXP-htE

MOR_AL

[Emersonpaz]

I bought CD4538 ICs for a Delta Pulse I was building, the pulse times were less than 50% of normal values. I think they are fake, or they have different characteristics to the ones I used before, I don't know.

I had the same problem with this CD4538BE on the Delta Pulse it was showing 22us where it should be 45us according to the original project, I compensated by changing the 1n5 capacitor to 4n7 sampling at 41us, yes the internal calculation differs from the datasheet.

[Jose]

I had the same problem with this CD4538BE on the Delta Pulse it was showing 22us where it should be 45us according to the original project, I compensated by changing the 1n5 capacitor to 4n7 sampling at 41us, yes the internal calculation differs from the datasheet.

I solved it the same way, thanks for sharing the information.