Integrated Bluetooth® audio ROM platform with Qualcomm® aptX™ audio and Qualcomm® cVc™ noise cancellation technology.

The CSR8645 dual-mode ROM audio SoC is designed to offer extensive voice and music capabilities in a ROM-based package, including aptX and cVc, making it ideal for a variety of wireless audio products with support for voice and music. The CSR8645 is part of the CSR86xx portfolio, a range of silicon platforms for wireless audio applications which integrate a dual-mode Bluetooth radio, a low power DSP, an application processor, a battery charger, memory and various audio and hardware interfaces into a single-chip solution. Developed for entry-level to mid-range wireless audio devices, the CSR8645 SoC supports cVc voice processing technology and aptX codec technology to deliver high quality voice and music capabilities in a costefficient ROM-based single-chip package. The CSR8645 is an easy and cost-effective platform for developing wireless audio products and supports reduced development time. It is an ideal solution for a range of highly differentiated home entertainment and wearable audio products including stereo headphones, speakers, speakerphones, headsets and hands-free devices.

CSR8645, Qualcomm aptX, Qualcomm cVc and Qualcomm Kalimba are products of Qualcomm Technologies, Inc., and/or its subsidiaries.

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Product Brief

High performance audio with aptX technology

aptX audio technology supports high-quality wireless audio, bringing pro-audio quality to consumer electronic devices.

Integrated single-chip solution for smaller designs

Application processor, Bluetooth and Bluetooth low energy radios, DSP and memory integrated into a single SoC helps reduce system complexity and eBOM while supporting small form factor designs.

No software development required

Pre-loaded Bluetooth and audio applications allow manufacturers to develop end-products without writing code, while customization tools support quick modification of device behaviour and user interface.

cVc 6th generation 2-mic audio technology

cVc technology is a suite of algorithms designed to work on the transmit and receive path of voice calls to deliver optimum voice quality on Bluetooth headsets, handsets, hands-free devices, and automotive.

CSR8645 Block Diagram


  • Bluetooth 4.0 specification compliant

  • Flexible ROM-based platform with fully configurable MMI and tool chain

  • Support for various profiles including: HFP 1.6, A2DP 1.2 AVRCP 1.4

  • 80MHz Qualcomm® Kalimba™ DSP with integrated multipoint A2DP and HFP audio applications

  • 2-mic cVc 6th Generation voice processing technology with wideband speech

  • Audio tuning suite with audio enhancements and 5-band EQs

  • Internal ROM, serial flash memory and EEPOM interfaces

  • aptX, MP3, AAC and SBC audio codecs

  • GAIA V1 and associated Android and iOS apps for connectivity with mobile devices

  • Reference speaker and headset applications pre-loaded on the ROM

  • Fast charging support up to 200mA with no external components

  • Pin compatible with CSR8640



DSP Technology: Qualcomm® Kalimba™ DSP


MCU Clock Speed: 80MHz MCU


Bluetooth Version: Bluetooth 4.1

Bluetooth Profiles: HFP v1.6, AVRCP v1.4, A2DP v1.2, DI v1.3, HSP v1.2

A2DP multipoint support: 2 A2DP sources

Bluetooth Radio: Up to +9dBm output power (typical), -92dBm receiver sensitivity (basic rate, typical)


USB Version: USB 2.0 (Full Speed)

USB Support: Supports USB charger detection

General Audio

Audio Technology: HD Voice, Voice recognition technology, Qualcomm® aptX™ audio technology, Qualcomm® cVc™ audio technology, Talk-Time Extension

Equalizer: 5-band EQ

HFP multipoint support: 2 handsets

Audio Recording

Microphone: 2 analog mics, 1 microphone bias generator, 2 digital mics

Power Management

Maximum Input Voltage: 3.3V


Maximum Current: 200 mA on chip, 500 mA with external transistor




Supported Interfaces: I²S, I²C, PCM, SPI, UART, USB 2.0




Maximum PIOs: 22

PWM (LED): 3


Package Type: VFBGA

Pitch: 0.5mm Pitch

Package Size: 5.5 x 5.5 x 1 mm