Bluetooth headset is the second largest application of Bluetooth. According to IMS's official market report, the overall global shipment of Bluetooth headsets was 67 million in 2007 and 81 million in 2008. Bluetooth headset is also the second largest Bluetooth device in the Chinese market. In addition, China is also the main manufacturing center of Bluetooth headsets in the world. It is estimated that more than 60% of the world's Bluetooth headsets are designed or produced by Chinese ODM / OEMs, including most top brands such as Nokia, Motorola and Samsung.
However, for the number of mobile phones with an annual output of more than 1 billion in the world, 80 million Bluetooth headsets are still very weak, especially today when Bluetooth has become the standard configuration of mobile phones. In other words, more than 90% of users with Bluetooth mobile phones do not use Bluetooth.
"This situation will change slowly. With more and more strict restrictions on drivers' use of mobile phones in various countries and more and more rich functions of Bluetooth headsets, the market prospect of Bluetooth headsets is very broad. However, there are four main technical reasons hindering the development of Bluetooth headsets, especially stereo headsets." Said Wu songru, CSR China Manager.
Then, he further explained as follows: first, the price of stereo Bluetooth headset is still expensive. Specifically, at present, the price of stereo Bluetooth headphones is more than twice that of mono headphones, and the price of some professional stereo headphones is higher;
Second, at present, the power consumption of stereo headphones is large, resulting in poor applicability. For example, the mainstream stereo headphones in the market can only play for 1 ~ 2 hours, but now mobile phones can play MP3 / MP4 for more than 5 hours, so the playing time of headphones is shorter than that of mobile phones;
Third, there are few stereo headphone schemes at present, and there are not many ODMs that can design good stereo headphones. Most ODMs focus on mono headphones;
Finally, due to the problem of decoding and conversion, stereo headphones are inferior to wired headphones in audio playback quality.
"Due to the above four reasons, there are still very few users of stereo headphones." Wu songru said, "therefore, CSR has improved these problems and launched the latest stereo headset scheme - bluetunes ROM, which realizes the best headset scheme on bc5 multimedia chip."
Specifically, bluetunes ROM has realized the following improvements: first, the flash circuit required by the original headset is changed to ROM circuit, which provides a direct method for users. CSR puts most of the things previously developed by customers in ROM, so that customers can quickly launch products. At the same time, due to the use of ROM instead of flash, the cost is also reduced a lot. The second improvement is that MP3 decoding and SBC decoding are directly integrated in bluetunes ROM, so that the headset can be played directly in MP3 format, which has higher sound quality than the current SBC format, and the signal-to-noise ratio can reach 95dB; At the same time, because there is no need to transcode at the mobile phone and headset end, the power consumption at both ends is greatly reduced. Thirdly, the unique faststream technology of CSR is adopted to shorten the delay of Bluetooth transmission. "If this technology is not adopted, the delay can reach 200ms. After adoption, the delay can be reduced to 28 ~ 34ms. Therefore, it can well solve the problem of audio-visual asynchrony in headphones." Fourth, bc5 multimedia integrates DSP, which can eliminate CVC echo and noise. "Many users report that the Bluetooth headset can not eliminate the surrounding noise when making a call. Our new scheme can solve this problem." Wu songru said. Its single microphone can achieve 10dB noise suppression; Preset optional dual microphone up to 30dB suppression. Finally, bc5 multimedia is a highly integrated solution with built-in DSP and RISC processor, stereo decoding, battery charging management, Bluetooth RF and Rom. customers only need to plug in a crystal oscillator to complete the design of stereo headphones, so the cost can be greatly reduced.
"With this new scheme, the cost of stereo headphones can be reduced by more than 50% Wu songru said, "moreover, a 180 MAH battery can play music for up to 10 hours. If you run CVC software to talk, you can talk for 12 ~ 16 hours."
According to Wu songru, CSR currently accounts for more than 80% of the global headphone chip shipments. As of April this year, CSR's shipments in the headphone market have reached 150 million. "Our earphone scheme has IOT test with mainstream mobile phones, and there is no problem with compatibility." He said.
In fact, because MTK makes Bluetooth the standard configuration of its mobile phone platform, the future market growth point of independent Bluetooth chip manufacturers will come from markets other than mobile phones, and headphones will be their biggest opportunity. Therefore, in addition to CSR, other Bluetooth chip manufacturers also pay great attention to the market, such as accel semiconductor. Shen Zhiqiang, marketing director of the company, said that they were about to launch a stereo Bluetooth headset scheme. "In addition to mobile phone Bluetooth headset and MP3 / MP4 Bluetooth headset, Bluetooth stereo audio application, Bluetooth hands-free device, Bluetooth video application and medical application are very good market opportunities in the near future."
