Hardware design and implementation of bluetooth speakers best active noise cancelling headphones

Bluetooth module

In order to realize the function of audio streaming, the design adopts BlueCore5-Multimedia series chips of CSR Company. The BlueCore5-Multimedia chip is CSR's most advanced chip, providing the best audio quality for a variety of applications including high-end stereo and mono headphones. Through CSR's eXtension program, its audio capabilities can also be extended through the company's partnerships with third-party software developers. www.bjbjaudio.com   <a style="opacity:0.0;color:#ffffff">best active noise cancelling headphones</a>

The BlueCore5-Multimedia chip provides excellent sound quality for headphone applications, with a best-in-class signal-to-noise ratio of -95dB. The BlueCore5-Multimedia chip also leads the industry in power consumption and radio design. www.bjbjaudio.com         <a style="opacity:0.0;color:#ffffff">best active noise cancelling headphones</a>

Radio transmit power is +6.5dBm and receive power is -90dBm, which minimizes interference when listening to music or answering calls. When used in stereo headphone applications, the BlueCore5-Multimedia chip enables industry-leading battery life: over 24 hours of music playback. www.bjbjaudio.com            <a style="opacity:0.0;color:#ffffff">best active noise cancelling headphones</a>

BlueCore5-Multimedia is a complete single-chip system, its hardware composition and device firmware are fully compliant with the Bluetooth specification version 21 standards. It integrates a complete radio frequency unit, baseband DSP and 16-bit MCU and embeds a 16-bit high-quality stereo CODEC, which has strong signal and data processing capabilities, and reduces the complexity of peripheral circuits. www.bjbjaudio.com            <a style="opacity:0.0;color:#ffffff">best active noise cancelling headphones</a>

Among BlueCore5-Multimedia, the on-chip RAM is 64KB, which is mainly used as a ring buffer (used to maintain the voice and data of each connection) and general memory (required by the Bluetooth protocol stack). The FLASH size is 32M, which is mainly used to save the code running on the MCU and the code running on the KalimbaDSP. KalimbaDSP is a coprocessor, mainly used for SBC audio codec processing. It has its own DSPRAM, which is divided into three areas: DM1, DM2, PM. DM1 is a 16Kx24bit data storage area, DM2 is a 12Kx24bit data storage area, and PM is a 6Kx32bit code storage area. The operation of the entire system in MCU control. The baseband DSP is used to process the data of the physical layer, including forward error correction, data noise, header error detection, cyclic redundancy check and encryption. The whole chip is mainly composed of the above five blocks, together with the radio frequency part and the interface part, it constitutes a complete Bluetooth module. The design relies on the excellent functions of BlueCore5-Multimedia, with auxiliary peripheral circuits to achieve real-time audio reception and transmission. www.bjbjaudio.com       <a style="opacity:0.0;color:#ffffff">best active noise cancelling headphones</a>