LONDON (Reuters) - British chip designer ARM has unveiled details of its first 64-bit architecture, which it said would expand its reach into enterprise applications such as servers currently dominated by Intel.

The ARMv8 architecture includes instruction sets for both 32-bit processing, which is used in the chips that power Apple's iPad and new iPhone 4S, and 64-bit processing, ARM said on Thursday.

Architecture based on 64 bits can handle more memory and larger files than 32-bit systems, and as such it is necessary for demanding applications such as scientific research and searching large databases.

Intel's 64-bit products include its Core processors used in PCs and its Xeon processors, which power multi-core servers and workstations.

ARM's CTO Mike Muller said the new architecture would enable the Cambridge-based company's chip-making partners to bring energy-efficient solutions to 64-bit processing markets.

Dan Vivoli, senior vice president at ARM licensee Nvidia, said: "The combination of Nvidia's leadership in energy-efficient, high-performance processing and the new ARMv8 architecture will enable game-shifting breakthroughs in devices across the full range of computing - from smartphones through to supercomputers."

ARM's low-energy 32-bit designs dominate processors in mobile phones and tablet computers, and are increasingly found in products ranging from toys to air conditioners.

ARM said a number of its partners were already working on the 64-bit ecosystem.

Nvidia said in January it was developing processors for PCs, servers and supercomputers based on ARM's architecture under the title "Project Denver".

(Reporting by Paul Sandle; Editing by Will Waterman)