We are pleased to announce that as of August 13, 2015, Qualcomm Global Trading Pte. Ltd., a subsidiary of Qualcomm Incorporated, has completed its acquisition of CSR plc. For more information, please see the press release .


CSR8640™ is a 2 mic stereo ROM solution targeted at mid-range Bluetooth® stereo headsets.

Customers can use CSR8640 to more easily, quickly and cost effectively bring to market a range of highly differentiated home entertainment and wearable audio products.  

Get this product


Market leading features in ROM

  •  Bluetooth 4.1
  •  HFP1.6, A2DP1.2 and  AVRCP1.4
  •  HD voice (wideband speech)
  •  Wired Audio (USB and Analogue)
  •  AAC-LC, MP3 and SBC decoders
  •  Multi-band EQ (up to 6 x banks)
  •  Headphone stereo separation (soft 3D)
  •  iOS battery status monitor
  •  Smart Apps support (GAIA)
  •  Multi-Language programmable audio prompts
  •  Simple speech recognition
  •  Configurable LED drivers
  •  6th gen dual-mic cVc®   NR / AEC algorithms
    •  2-mic Far-end NR / AEC algorithms
    •  Frequency enhanced speech intelligibility (FESI)

Flexible ROM based platform

  •  Fully configurable MMI and tool chain

Package options

  •  5.5x5.5mm, 68-pin BGA (0.5mm pitch)
  •  Pin compatible with CSR8645

Key Feature

Customer Value

Consumer Value

Wired Audio & Full USB Support


Wired as well as wireless.

Extends use of headset to devices that don’t have Bluetooth

Can listen and charge – enjoy both a wireless and a wired experience – charge AND do

Multi-Band EQ

Volume Boost


Fully configurable & tunable EQ enabling multiple presets for Rock, Jazz, Classical, Dance etc

Dynamic bass boost

Different types of music sound equally great.

Music doesn’t distort, even when it’s loud

Bi-directional Noise Reduction


NR benefit to the headset user

Customer satisfaction with conversation quality

Conversation is clear and effortless

3 LEDs

Wide range of UI options.

Clearer and more extensive display of status information.

Smart Apps Support (Using GAIA)

Use Apps for product differentiation

Create new revenue stream

Rich User experience

Interactive accessory via Apps

Personalisation via Apps

Rapid Charge Support


Support higher charge currents and eliminate need for external battery charger

Charge your stereo headset much more quickly


Terms of Supply