Strange organic PCB design on dismantled 8GB SD Card

[cybergibbons]

My girlfriend managed to damage an SD card so that it wouldn't work in her camera, so I decided to pull the plastic cover off to see what was inside. The plastic case is much larger than the board, and at first looked boring - it just looked like a flat encapsulated PCB with some ripples on the potting compound.

However, under oblique light and magnification, it shows that the board has a really interesting, organic design. I've taken a lot of things apart and never seen anything quite like this.

Link to full size

LEECH666 pointed out this autorouter which has similar results:
http://www.eremex.com/products/topor/

Anyway, I thought it was interesting. Has anyone else seen this? Got any ideas why?

[AntiProtonBoy]

I love Bezier traces, they look nice. I guess one reason to use something like that is to give you more compact routes. Vintage (cold war era) electronics use similar routing styles, particularly Russian stuff.

[mikeselectricstuff]

I think it allows for the maximum density for a given set of PCB design rules and layers - one claim of the topological router linked above is it allows fewer layers.

[BravoV]

LEECH666 pointed out this autorouter which has similar results:
http://www.eremex.com/products/topor/

Anyway, I thought it was interesting. Has anyone else seen this? Got any ideas why?

Interesting, thanks for the link, just knew such application exist.

Did browse that website, found a particular interesting feature here -> http://eda.eremex.com/products/topor/competitiveadvantages/electromagnetic.html  its about the sharp pointy right angle trace vs rounded one that they claimed rounded corner is better.

Just fyi, Dr.Howard Johnson (the author of the "High Speed Digital Design: A Handbook of Black Magic") said its a myth, and it makes no big difference at all for signal integrity for single ended trace, not differential though. Dave actually did ask him specifically about this in The Amp Hour #77, highly recommended if you haven't listened.

[ronwoch]

^^Myth or not, it sure looks cool!

[Spiro]

Yeap. 

[Jope]

Great photo!
What brand is the SD card?

[cybergibbons]

Externally branded PNY, internally seems to be Sandisk.