Patent · US Active

FPGA having low power, fast carry chain

US8044682B2 · kind B2 · utility

7Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 1, 2009
Grant dateOct 25, 2011
Priority date
Expiry dateAug 4, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/17784
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An in-FPGA carry chain is provided that does not exhibit significant leakage current. In particular, parts of the carry chain can be switched on/off when desired. In this manner, carry chain parts can have their leakage currents substantially disabled when they are not in use, thus saving power. Additionally, there is provided a carry chain whose logic is separate from the other parts (e.g., LUTs) of the logic blocks that perform the remaining arithmetic functions, and whose inputs are the input data to be added, rather than data that is output in delayed fashion from the other parts (e.g., LUTs) of the logic blocks. Such a configuration reduces latency by allowing the carry chain to operate directly on the received input data without need to wait on results from the other parts (e.g., LUTs) of the logic blocks.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.