HP Forums

Hi, my name is Pablo and I have an Hp41c calculator in my small collection that had a dead logic board. So I decided to decap and expose the die of every IC chip in the calculator and I want to share the photos with you, I know some of you will be interested. I don't know how to post the photos on this forum I will try, but you can see them in my twitter acount @walls_pablo.

Pablo Walls

Hei Pablo,

you can post links to photos hosted somewhere else. If your intention is to have photos that can be used to reverse-engineer the parts, well they will be quite large and cannot be hosted here anyways. (Use the small button on the toolbar of the editor with what looks like a red sun and a blue mountain, it has the caption "insert image").
For small photos use the button "Choose File" on the lower left corner of the "Attachmet" block.

Thank you Alejandro for your reply, now I know why I could not attach any photo.

Pablo walls

Die shot from a DC-DC converter from a Hp-41C calculator, part number 1826-0953-1.

Inside the hp41c calculator, this time was able to decap and expose the die of one of the RAM chip's (ILE701) and one of the ROM's (ILE908), next time I will try to decap the display drivers.

RAM chip's (ILE701)

The ILE908 ROM from the Hp41c.

The CPU from the Hp41c.

Finally, I was able to decap and expose the die of one of the display driver's of the Hp41c calculator.

I was surprise to find out that the display drivers look to be more complex than the CPU.

This is sad for the calclulator but the photos still are beautiful.

(03-21-2018 02:15 PM)pablowalls Wrote: [ -> ]Die shot from a DC-DC converter from a Hp-41C calculator, part number 1826-0953-1.

Very nice, what equipment did you use to take the die shots? I have taken die shots before using bellows with a reversed lens and also using microscope objectives adapted to my camera.

Paul.

Hi Paul, I did not use any special adapter, just my cell phone over the objective lens of the microscope.

Pablo Walls

(03-21-2018 02:45 PM)damaltor Wrote: [ -> ]This is sad for the calclulator but the photos still are beautiful.

Damaltor, this calculator was beyond repair and I thought it would be interesting to see inside the chips that make this calculator tick, I did the same with an Hp25 but was the first one I try to Decap with very bad results. I have an Hp67 with a bad ACT chip and I will try to decap and hope this time I get it right.

(No live HP calculators were harmed in the making of this post, they were already dead.)

Very cool, thanks for sharing these.

Also, thanks for your policy of not harming working machines.