AMD as well as Nvidia are being sued by Power Management Solutions over one of the most basic power management functions in integrated circuits used today.
Power Management Solutions, a Frisco- Texas-based company with no traceable corporate history, claims that it is entitled to damages relating to patent number 5,504,909, which the company says is infringed by AMD and Nvidia.
The patent, titled "Power management apparatus collocated on the same integrated circuit (IC) as the functional unit that it manages" was filed by Electronics Products Company in January 1994 and approved by the USPTO in April 1996. Power Management Solutions claims it has the rights to the patent, even if the USPTO did not list Power Management Solutions as the rightful owner at the time of this writing. Intel and Freescale were sued by Power Management Solutions over the same patent back in August of last year. There is no information on the proceedings of these cases.
The patent in question describes the idea to control electricity flow via on and off switches "between the co-resident functional circuit I/O nets and the integrated circuit I/O pads" as well as between internal and external ICs. The basic idea covers power being routed "from an external power supply through the power gating means to the internal functional circuit" using switches and a second electrical signal is being employed to control "the coupling action in the power gating means."