ARM Cortex-M0+ Is The World's Most Energy-Efficient Microprocessor

* Says new 32-bit chip more power efficient

* Licenses to Freescale and NXP Semiconductor

LONDON, March 13 (Reuters) - British chip designer ARM has unveiled what it said was the world's most energy-efficient microprocessor design that will help devices ranging from fridges to medical equipment to parking meters to communicate with other devices.

Cambridge-based ARM, best known for creating the processor technology that powers nearly all of the world's smartphones and tablets, said its new 32-bit design used about one third of the energy of 8-bit or 16-bit microcontrollers available today.

Low-cost microcontrollers are already embedded in millions of devices like household appliances, cars and toys, where they monitor and control performance.

Moving to low-energy 32-bit technology will help machines to communicate with other machines, ARM said, laying the foundations for the so-called "internet of things" that will wirelessly connect devices that little resemble today's PC, tablets and smartphones.

The new Cortex-M0+ processor had already been licensed to chipmakers Freescale and NXP Semiconductor, ARM said on Tuesday.

Microcontrollers are a fast growing source of revenue for ARM, with some 1 billion of the chips based on its blueprints shipped in the fourth quarter of 2011 alone, up 40 percent on a year earlier.

ARM receives a royalty of 1-2 percent on each chip. A microcontroller based on the new design would typically sell for about 20 cents, it said, which adds up to a significant sum considering the many millions of chips shipped.

It competes with companies including Renesas and Microchip Technology in microcontrollers.