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www.lairdtech.com
Laird Technologies
BTM520/521
Bluetooth
®
Multimedia Plus Module
The BTM520 and BTM521 are the most advanced low power, multimedia Bluetooth
modules on the market. They have been designed by Laird Technologies to meet the needs
of developers who require the ultimate Bluetooth audio performance and flexibility, along
with fast time to market. The modules include everything needed for a fully qualified
and functional Bluetooth multimedia application. As well as providing best in class radio
performance, range and power consumption, they support all of the functionality to run
Cambridge Silicon Radio’s Road Tunes and Blue Tunes development environments. They
support the latest Bluetooth Version 2.1+EDR Specification, providing the important advantage
of Secure Simple Pairing, which improves security and enhances the ease of use for end
customers. The BTM521, with an integrated high performance multilayer ceramic antenna
can achieve open field ranges in excess of 300 metres.
The modules include a 16 bit stereo codec and microphone input to support both stereo and
mono applications, with the ability to drive 16
Ω
stereo speakers. They also contain all of
the necessary audio filtration and biasing components, so that the module only requires the
addition of speakers, microphone and push buttons to make a complete implementation.
The modules contain a full, integrated Bluetooth stack along with SPP, HFP 1.5, HSP, AVRCP
and A2DP profiles, all of which have been qualified, so that no further Bluetooth qualification
is required. For users with more complex applications, additional profiles will be available for
file transfer, object exchange, dial up networking, messaging and phone book control. Future
support also includes the Health Device Profile, making this the ideal module for development
of Continua compliant medical devices. Because these modules are pre-qualified, customers
using these modules can list and promote their products on the Bluetooth website free of
charge.
The BTM520 and BTM 521 modules include an embedded 32 bit, 64 MIPS DSP core within
the BC05, which is integrated with the Bluetooth functionality and which allows designers
to add significant product enhancements. These include features such as echo cancellation,
noise reduction and audio enhancement using additional soft codecs. 16MB of flash memory
is available within the module, so that complex functionality can be included. DSP routines are
licensable from a number of specialist partners. Typical applications for these modules include
Bluetooth headsets, Bluetooth stereo headsets, VoIP phones, automotive products, wireless
audio links and medical / healthcare devices.
To speed product development and integration, Laird Technologies has developed a
comprehensive AT command interface, which simplifies application development and includes
support for audio and headset functionality. It provides access to GPIO pins, allowing these
to be mapped for direct connection to actuator buttons on headsets. Combined with a low
cost developer’s kit, this ensures that the choice of Laird Technologies Bluetooth modules
guarantees the fastest route to market.
OVERVIEW AND
KEY FEATURES
