SoC designs threatened by PalmChip bus patent

Prior art challenge

PalmChip has warned fellow system-on-a-chip specialists that it now holds a key patent in the design of the buses that connect on-chip units and suggested they check their own technologies for signs of "conflict".

The company was granted the patent, number 6,601,126 on 29 July. It was filed in May 2000.

Entitled 'Core-chip framework for systems-on-a-chip', the patent covers "a system-on-chip interconnection structure and method [that] uses unidirectional buses only, central shared memory controllers, separate interconnects for high-speed and low-speed peripherals, zero wait-state register accesses, application-specific memory map and peripherals, application-specific test methodology, allowances for cache controllers, and good fits with standard ASIC flow and tools."

With the patent now officially recognised, PalmChip is out to let everyone know. "Our first phase is to inform the SoC industry that we have been granted this patent," said James Venable, PalmChip's VP of marketing, according to an EE Times report. "We want to give companies that are creating on-chip buses an opportunity to examine their technology to see if there is a conflict and then, if there is, to contact us.

"We intend to be co-operative about this, not punitive," Venable offered. "But of course we will defend our patent aggressively."

According to the detailed EE Times story, PalmChip's patent claims cover a great many of the SoC designs on the market today. Those claims cover key aspects in the development of modern SoC on-chip buses, and what's probably the best method of implementing those buses.

While that sounds like PalmChip now 'owns' a crucial part of many SoC designs, there's a clear feeling that the uni-directional bus described by the patent is something almost all SoC designers had decided was the way forward and had begun to work on by the time the company filed its patent application.

Prior art is likely to play a strong part in any company's defence against demands made by PalmChip that it recognise the ownership of the technology outlined in patent 6,601,126. ®

Related Link

PalmChip bus patent threatens most SoCs