The Trojan Horse Was Free Too

Timeo Danaos et dona ferentes. I fear the Greeks especially when bearing gifts. In Virgil’s Aeneid these words are spoken by the Trojan priest Laocoön warning about the wooden horse that the Greeks have offered Troy. But to no avail, Laocoön is slain by serpents and the Trojans bring the horse inside the walls of Troy. Since the horse was full of Greek soldiers this turned out to be, shall we say, sub-optimal.

The free eFuse cell from foundries can be sub-optimal too. Is it a just a gift or a Trojan horse. While it is going too far to fear the foundries when they are bearing gifts of free IP, in the case of eFuses they do come with their own set of problems hidden inside. This is especially so as we get down to small process geometries. At 16nm and below the eFuse cell is getting so large that it threatens to dominate the chip in designs that require large NVMs. A much more practical choice is to use an antifuse approach. With lower power and higher speed, and with 1/300th of the area, what’s not to like?

When you start to take security into account, and many NVMs are used for holding serial numbers, encryption keys and the like, then antifuse becomes even more attractive. eFuse bits can be read out by looking at the bit cells to see if the fuse is blown or not. Antifuse stands up to even the most vigorous and destructive attempts to read out the programmed value, not just to commercial standards but military too.

One more big advantage is that the antifuse-based NVMs do not require special power supply voltages and so can be programmed after packaging, whereas eFuse-based memories normally have to be programmed on the wafer before they are packaged. Programming after packaging can make supply chain management a lot easier since there are many applications where the code to be programmed is not known until late in the manufacturing cycle.

If Orange is the New Black then Antifuse is the new Fuse. Kilopass will be on three booths at DAC next week showing various aspects of their antifuse NVM technology and why it is the NVM bitcell for the future.

Tney will presentAntifuse Memory: The New NVM Foundation IP in the ChipEstimate booth (#2433) on:

• Monday, June 8, at 1:30 p.m.
• Tuesday, June 9, at 11:30 a.m.
• Wednesday, June 10, at 2:30 p.m.

They will demonstrate in the ICScape Booth (#1602) how ICScape’s design tools have contributed to Kilopass’ development of a wide range of NVM IP’s ultra low-power and high-performance features, fast access speed, megabits of capacity and more than 10 years of data retention.

In the TSMC Booth (#1933), Kilopass will showcase its NVM IP’s availability on all TSMC process nodes from 180nm to 20nm and offer a look at how antifuse technology is the future NVM foundation IP, replacing eFuse below 16nm. Their sessions are scheduled for:

• Monday, June 8, at 2:15 p.m.
• Tuesday, June 9, at 4:45 p.m.
• Wednesday, June 10, at 10:15 a.m.