sue you, sue me

J.D. McEachin jdm at
Tue Apr 2 22:11:28 CEST 1996

On Tue, 2 Apr 1996, Matt Haines wrote:

> We've all heard how Roland was possibly sued over borrowing Moog ladder
> technology for their filters, but replacing transistors with diodes instead
> (or whatever it is, don't flame me for the details). What would have
> happened if Roland had put those diodes on a chip? Or for that matter, put
> a transistor ladder on a chip? How would Moog be able to prove it if the
> thing's burned into an IC? You can't just pop the hood of a synth and look.
> I ask because I was looking at the schems of my SH101, and they use a
> proprietary filter chip. But the bits outside the chip look a bit
> ladder-ish, and I started wondering if they'd gotten away with something.
> So how could anyone tell?

It can be done, if you have the bucks.  It requires a clean room, an 
electron microscope, and some specialized probing equipment, though I bet 
w/ something as simple as a filter chip you could get away w/ just less.  
ICs are still pretty 2D, so just looking at a magnified image can tell you 
something about its workings if you know what to look for.  With the 
probes you can check out what's going on in various parts of the circuit.

Believe me, when AMD puts out a CPU chip, Intel takes a long hard look at 
what's inside.


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