MIPI Alliance updates its MIPI SLIMbus spec

The MIPI Alliance, an international organization that develops interface specifications for mobile and mobile-influenced industries, announced an update to MIPI SLIMbus, a specification used to interconnect audio components in mobile and mobile-influenced devices. The new release, v2.0, adds new features that address the market’s needs for increasingly sophisticated audio performance while simplifying component integration for manufacturers.

“MIPI Alliance is continually engaged with the market to identify new requirements for audio interface technologies and the updates provided in MIPI SLIMbus v2.0 were developed in direct response to emerging market needs,” Joel Huloux, Chairman of the Board of MIPI Alliance. “In particular, with v2.0, companies can optimize multichannel sound transport to support new functionalities, better audio quality or better user interaction in their mobile terminal designs.”

MIPI SLIMbus is a two-wire hardware interface and transport protocol that was developed by the MIPI Alliance Low-Speed Multipoint Link Working Group (LML WG) and introduced in 2007. The specification supports a wide range of digital audio and control solutions to seamlessly transport audio and related data for larger-sized mobile device components, such as the application processor, audio codec, modem, audio digital signal processor, Bluetooth, and FM receiver.

The v2.0 release introduces three key features. One feature is a new approach for multiline configuration that increases bandwidth scalability. Another feature is multichannel capability that can transmit multiple, phase-aligned audio streams between multiple devices and peripherals; the multichannel feature can also support phase-coherency, improved direct memory access (DMA) efficiency, and higher bandwidth via a reduced number of ports to simplify integration and improve use of limited board space in a device. A third feature is a segment distribution technique that uses new secondary data transport lines to maximize the use of available bandwidth for asynchronous data transmissions; this feature can improve performance for pushed or pulled data, software downloads, audio uploads or bulk data transport.

MIPI SLIMbus v2.0 is also backward compatible with previous versions of the specification. MIPI Alliance offers MIPI SLIMbus in addition to MIPI SoundWire?, an interface used to support very small audio peripherals such as amplifiers and microphones. MIPI SLIMbus can coexist with MIPI SoundWire or non-MIPI interfaces through bridging solutions.

Lior Amarilio, vice chair of the MIPI LML WG and wired connectivity architect at Qualcomm, said the broadened capabilities and implementation flexibility offered by the updated MIPI SLIMbus specification will enable designers to use this single means of transport to quickly interconnect multiple audio components on the same link. The specification also supports software configuration, which enables system flexibility. The techniques facilitate interoperability, reduce time-to-market and lower design costs by simplifying the interconnection of products from different manufacturers.