Analog Devices 45K (AD45K?)
 

Anyone know what this is?

Dr Google is unhelpful.

Package is about 28mm square with 5 and 2 pins on underside.

Acquired along with a few other interesting bits and pieces- egg 2N491B and 2N502 .....

Re: Analog Devices 45K (AD45K?)
 

There's a model 45k mentioned in here as an Op Amp (LH column...Mag page 15...focused glasses may be required..):

https://www.analog.com/media/en/anal...e5-number3.pdf

Lawrence.

Re: Analog Devices 45K (AD45K?)
 

Your eyes must be better than mine- I'd skimmed through that document as just about the only useful looking search result.

Pity I can't return the card with C12 circled!

Adding op amp to the search turned up an Analog Devices OP amp history section in their OP Amp Applications book which identified the 45 (presumably a forerunner of the 45K) as a FET input fast settling opamp.

Haven't found a spec yet though.....