Bluetooth 4.0 CSR8645 Amplifier Board 5W+5W APT-X Stereo Receiver Amp Module

The Bluetooth 4.0 CSR8645 Amplifier Board is a compact dual-channel stereo receiver amplifier module delivering 5W+5W RMS output with integrated APT-X audio codec support for superior wireless audio quality. Audio engineers, DIY enthusiasts, and embedded systems developers use this module to build wireless speaker systems, portable audio devices, and IoT-enabled sound solutions with minimal component count. This product solves the critical challenge of integrating high-fidelity Bluetooth audio reception with Class D amplification in space-constrained applications while maintaining low power consumption and excellent audio clarity.

Product Overview

The CSR8645 chipset represents Broadcom's advanced Bluetooth audio solution, combining a powerful Bluetooth 4.0 transceiver with integrated digital signal processing and stereo amplification capabilities. This module operates on a single 5V power supply and implements Class D amplification topology, which delivers exceptional efficiency with minimal heat generation compared to traditional linear amplifiers. The APT-X codec ensures lossless audio transmission at 352kbps, providing studio-quality sound reproduction that surpasses standard SBC Bluetooth audio codecs. The board features integrated filtering, protection circuits, and thermal management, making it production-ready for commercial and hobbyist applications alike.

The module's architecture eliminates the need for external Bluetooth stacks and complex audio processing chains, significantly reducing development time and bill-of-materials costs. The CSR8645 supports both A2DP (Advanced Audio Distribution Profile) and AVRCP (Audio Video Remote Control Profile), enabling seamless playback control from paired devices. With a typical operating range of 10-15 meters in open space and support for simultaneous connection of up to 7 Bluetooth devices, this amplifier board is ideal for multi-zone audio systems, wireless headphone amplifiers, and portable speaker designs. The low-noise design and integrated power management deliver clean audio output with THD+N below 1% at rated power.

Key Specifications

Specification	Details
Product Type	Bluetooth 4.0 Stereo Receiver Amplifier Module
Chipset	CSR8645 (Broadcom)
Bluetooth Version	Bluetooth 4.0 with BLE Support
Audio Codec	APT-X, SBC, MP3
Output Power	5W+5W RMS at 4 Ohms (10W Total)
Amplifier Class	Class D
Operating Voltage	5V DC (USB Powered)
Frequency Response	20Hz to 20kHz
THD+N	Less than 1% at rated power
Signal to Noise Ratio	Greater than 90dB
Bluetooth Range	10-15 meters (open space)
Simultaneous Connections	Up to 7 devices
Board Dimensions	85mm x 50mm x 20mm
Weight	Approximately 45 grams
Origin	Original/Authentic
Warranty	7 days on manufacturing defects
Shipping	1-5 days from Bengaluru
Delivery	7-8 days across India
Support	24/7 via Email and WhatsApp

Key Features

• CSR8645 Chipset: Integrated Bluetooth 4.0 transceiver with built-in DSP eliminates need for external Bluetooth modules and separate audio processors
• Dual-Channel Stereo Amplification: 5W+5W Class D amplifier delivers 10W total output with exceptional efficiency and minimal thermal dissipation for compact enclosures
• APT-X Audio Codec Support: Lossless wireless audio transmission at 352kbps ensures studio-quality sound reproduction superior to standard SBC codec
• Single 5V Power Supply: USB-powered operation simplifies integration into portable devices, eliminating need for complex multi-voltage power management
• Low Noise Design: Signal-to-noise ratio exceeding 90dB and THD+N below 1% ensures clean, distortion-free audio output across entire frequency spectrum
• Integrated Protection Circuits: Thermal shutdown, overcurrent protection, and DC offset detection safeguard connected speakers and amplifier components
• Multi-Device Support: Simultaneous pairing with up to 7 Bluetooth devices enables flexible switching and multi-room audio configurations
• Compact Form Factor: 85mm x 50mm footprint fits into space-constrained applications while maintaining full functionality and audio quality

Applications and Use Cases

• Wireless Speaker Systems: Build portable Bluetooth speakers with high-fidelity audio output using this all-in-one receiver-amplifier solution for consumer audio products
• Car Audio Integration: Retrofit existing automotive audio systems with Bluetooth connectivity and amplified output for seamless smartphone music streaming in vehicles
• Home Audio Amplification: Create wireless multi-room audio systems by connecting this module to existing passive speakers in living rooms, bedrooms, and outdoor spaces
• Headphone Amplifiers: Design portable headphone amplifiers with Bluetooth input and Class D amplification for audiophile-grade listening experiences on mobile devices
• IoT Audio Devices: Integrate into smart home speakers, voice-controlled audio systems, and IoT devices requiring low-power wireless audio reception and amplification
• DIY Audio Projects: Hobbyist and maker projects including Bluetooth-enabled guitar amplifiers, vintage radio retrofits, and custom audio installations
• Commercial Audio Solutions: Professional installations in restaurants, retail stores, and hospitality venues requiring wireless audio distribution with minimal infrastructure
• Medical and Industrial Equipment: Audio feedback systems in medical devices and industrial monitoring equipment requiring reliable Bluetooth connectivity and amplified output

How to Use

Begin by connecting the module to a 5V DC power source through the USB connector or dedicated power pins on the board. Ensure proper speaker connections to the left and right amplifier outputs, using 4-8 ohm speakers rated for minimum 5W continuous power handling. The module enters pairing mode automatically on first power-up; use your Bluetooth-enabled device (smartphone, tablet, or computer) to scan for available devices and select the CSR8645 module from the Bluetooth settings. Once paired, the module will automatically reconnect to previously paired devices when powered on, establishing audio streaming within 2-3 seconds.

For optimal audio quality, enable APT-X codec in your source device settings if available, as this provides lossless audio transmission superior to standard SBC codec. Position the module within 10-15 meters of your Bluetooth source device to maintain stable connection and minimize audio dropouts. The integrated thermal management system operates silently without active cooling; however, ensure adequate ventilation around the board during extended use at maximum volume. For advanced applications, the module supports AVRCP commands, allowing volume control and track navigation directly from compatible Bluetooth remotes or headset controls. If experiencing connection issues, perform a factory reset by holding the reset button for 10 seconds, which clears all paired devices and returns the module to initial pairing mode.

Frequently Asked Questions

What is the difference between APT-X and SBC audio codecs on this module?

APT-X is a proprietary lossless audio codec that transmits audio at 352kbps with minimal compression, delivering near-CD quality sound reproduction. SBC (Subband Coding) is the standard Bluetooth codec that uses higher compression ratios, resulting in noticeable audio quality loss. The CSR8645 module supports both codecs; when connected to APT-X capable devices, it automatically selects APT-X for superior audio fidelity. Devices without APT-X support automatically fall back to SBC codec without manual intervention.

Can I connect multiple speakers to this amplifier board simultaneously?

The module provides two independent amplifier channels (left and right stereo), each capable of driving one 4-8 ohm speaker at 5W maximum. You cannot directly connect multiple speakers to a single channel without a speaker selector switch or impedance matching transformer, as this would reduce output impedance and potentially damage the amplifier. However, you can use passive speaker crossovers or active multi-amplifier configurations to drive multiple speakers from a single stereo source.

What is the maximum Bluetooth range and how can I improve connectivity?

The CSR8645 module has a typical operating range of 10-15 meters in open space with clear line-of-sight to the Bluetooth source device. Range decreases significantly through walls, metal structures, and other obstacles due to RF signal attenuation. To improve connectivity, position the module in elevated locations away from metal objects, minimize distance to source devices, and avoid operating near 2.4GHz microwave ovens or WiFi routers that cause interference on the same frequency band.

Is this module suitable for battery-powered portable applications?

Yes, the module is excellent for portable applications. It operates on a single 5V supply and draws approximately 200-300mA during playback at moderate volume, making it compatible with standard USB power banks and battery packs. For extended battery life, consider using a 5V lithium polymer battery with capacity of 2000-5000mAh, which provides 6-20 hours of continuous operation depending on volume levels and battery capacity.

When will I receive my order?

Orders are dispatched within 1-5 business days from our Bengaluru warehouse. Delivery takes 7-8 days to most locations across India.

What is your return and warranty policy?

We offer a 7-day return policy on manufacturing defects only. Contact support within 7 days of receipt for free replacement or full refund. Not applicable for user damage or misuse.

Are bulk discounts available?

Yes, wholesale pricing for orders of 10 or more units. Contact our sales team via WhatsApp or email for a customized bulk quote.

Why Buy from The Engineer Store

• Genuine Products: Sourced directly from authorized distributors with authentication
• Expert Team: Our technical team validates every product before listing
• Fast Shipping: Dispatched within 1-5 days from our Bengaluru warehouse
• Pan-India Delivery: 7-8 days to Mumbai, Delhi, Chennai, Hyderabad, Pune, Kolkata
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Buy Bluetooth 4.0 CSR8645 Amplifier Board 5W+5W APT-X Stereo Receiver Amp Module Online in India

Purchase the Bluetooth 4.0 CSR8645 Amplifier Board 5W+5W APT-X Stereo Receiver Amp Module online at The Engineer Store, India's trusted source for genuine electronics. We deliver across Bengaluru, Mumbai, Delhi, Chennai, Hyderabad, Pune, Kolkata, Ahmedabad, Jaipur, and Surat.

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