OPA541 High-Power-Opamp - Die pictures

[Noopy]

Hi all!

Perhaps you are interested in an OPA541 High-Power-Opamp:




The highside and the lowside power transistor(s) are huge!

It contains a ceramic plate which probably is made of beryllium oxide.

See everything here:
https://www.richis-lab.de/Opamp02.htm


Best regards,


Richard

[NiHaoMike]

It contains a ceramic plate which probably is made of beryllium oxide.

Definitely is, that's what the BeO marking on the cover means.

[Noopy]

It contains a ceramic plate which probably is made of beryllium oxide.

Definitely is, that's what the BeO marking on the cover means.

Most likely… 

[Noopy]

Since the OPA541 didn´t fill the topic here some pictures of the APEX PA88:

https://richis-lab.de/Opamp03.htm

Less current (100mA) but much more voltage (+/-250V).





It´s a nice hybrid.




And of course some die pictures. 




Does anybody know why they have put a silicon slice (only) under the Lowside-Output-Transistor?
Is that because of the p-channel depletion MOSFET? Because of the p in the channel? 


More pictures on my website.


 

[Noopy]

Are you interested in more Power-Opamps?

I have an ICH8530 for you:






Once more a berryllium oxide substrate.




Interesting solder joints... 




That looks like a crude laser trimming...




Nice MESA-transistors!


More pictures on my website:

https://richis-lab.de/Opamp04.htm

 

[Noopy]

...APEX PA88:
https://richis-lab.de/Opamp03.htm
...

A small update to the PA88:
In the datasheet all the transistors look like depletion MOSFETs but that´s wrong. The amplifier wouldn´t work probably with depletion mode MOSFETs. I exemplary probed Q8 and it´s a enhancement MOSFET:



I assume all the MOSFETs are enhancement MOSFETs.

[PartialDischarge]

The lightning, sharpness and depth of field of your pictures is amazing. What equipment do you use?

[Howardlong]

Truly fascinating!

[Howardlong]

The lightning, sharpness and depth of field of your pictures is amazing. What equipment do you use?

Good question!

Focus stacking maybe?

[Noopy]

We talked a lot about that here:
https://www.eevblog.com/forum/projects/decapping-and-chip-documentation-howto/

I use a normal camera with a 10-22mm lens reversed and some distance rings between lens and camera.



Then you need the right light and a lot of experience and here we go.
The tilted pictures are of course focus stacked. Often I have to take 20 or 30 pictures for one picture.