Product Description
This Bluetooth module uses CSR's advanced CSR8635 chip. Along with Bluetooth 4.0, the chip allows the delivery high-performace and high-quality audio in a cost-effective and small module. It can be used to simply receive streaming audio for remote speakers, or to receive and make calls through a paired phone. Features include:
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Built-in high-quality DAC converter circuit (95dB SNR)
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The built-in Kalimba DSP data processor provides powerful features including a variety of digital speech processing functions
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15 x 21mm module size
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Bluetooth 4.0
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Pre-programmed GPIO pins for media control (play, pause, skip etc)
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Less than 2ma operating current
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Class 2 RF power level: up to 20m transmission distance
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Call agreement through the HFP V1.6 profile
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Simple pairing procedure
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AUX input support
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RoHS compliant
Pin Descriptions
Pin # |
Pin Name |
Functional Description |
1 |
GND |
Ground |
2 |
GPIO15 |
Next Song / UART Tx / GPIO15 |
3 |
GPIO14 |
External amplifier mute control / UART Rx / GPIO14 |
4 |
RST |
External reset (active low) |
5 |
MOSI |
MOSI / GPIO2 / PCM1_IN |
6 |
CLK |
CLK / GPIO5 / PCM1_CLK |
7 |
CS |
CS / GPIO4 / PCM1_SYNC |
8 |
MISO |
MISO / GPIO3 / PCM1_OUT |
9 |
R_LED |
LED 1 |
10 |
B_LED |
LED 2 |
11 |
VREG |
Power On/Off / Pair Device / Answer Phone Call |
12 |
1V8 |
Internal regulator output |
13 |
VBAT |
Power supply / lithium Battery input (3.5V - 5V) |
14 |
Vsense |
Battery detection (can be left N/C) |
15 |
GND |
Ground |
16 |
MIC_BIAS |
Bias output for microphone |
17 |
AUX_RP |
Aux input (right channel, positive) |
18 |
AUX_RN |
Aux input (right channel, negative) |
19 |
MIC_LP |
Mic input (positive) / Aux input (left channel, positive) |
20 |
MIC_LN |
Mic input (negative) / Aux input (left channel, negative) |
21 |
GND |
Ground |
22 |
SPK_RN |
Speaker ouput (right, negative) |
23 |
SPK_RP |
Speaker ouput (right, positive) |
24 |
SPK_LN |
Speaker output (left, negative) |
25 |
SPK_LP |
Speaker output (left, positive) |
26 |
GPIO21 |
Play/Pause Control / GPIO21 |
27 |
GPIO18 |
Volume Down Control / GPIO18 |
28 |
GPIO7 |
Volume Up Control / GPIO7 |
29 |
GPIO6 |
Previous Song / GPIO6 |
30 |
GND |
Ground |
31 |
ANT |
External Antenna |
Application Notes
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Control inputs are active high and can be pulled up to the 1V8 output through a push button.
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The speaker outputs should be buffer through a suitable amplifier IC to drive any significant load.
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The microphone input needs suitable external biasing (using the MIC_BIAS output) in order to be effective.
Download the CSR8635 datahseet
The current ED8635 module has replaced our previous module that was based on OmniVision's OVC3860 IC. Below is the documentation for that module.
We have a few of these modules left in stock. If you are interested in them, please contact us.
Features:
The Bluetooth module utilizes OmniVision's OVC3860 Bluetooth 2.0 + EDR stereo audio processor allowing a user to stream audio from just about any Bluetooth device (such as a PC, mobile phone, etc.) to remote headphones, speakers or an amplifier. The OVC3860 IC transceives high-quality 20-bit stereo audio and incorporates an on-chip power management unit consisting of a switch-mode regulator, linear regulators and a Li-Ion battery charger.
The OVC3860 is fully Bluetooth 2.0+EDR compliant and its configurable Bluetooth stack is integrated with profiles and applications including A2DP v1.2, AVRCP v1.4, HSP v1.2 and HPF v1.5.
The module has a number of useful inputs and outputs including:
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Audio outputs (capable of directly driving 40mW @ 32Ω speakers)
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Status LEDs
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Li-Ion battery charger
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Media signals (Volume up, down and mute, Next, Prev etc.)
Specifications:
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Transmit power: 0 to +4 dBm
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Receiver sensitivity: -82 dBm @ 1% BER
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Supported profiles: A2DP (v1.2), AVRCP (v1.4), HSP (v1.2) & HFP (v1.5)
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Operating frequency: 2402-2480 MHz
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Supply voltage: 3.4 to 4.2 Vdc
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Current consumption: 26mA (active), <1mA (idle)
Instructions
Before you are able to begin streaming audio through the device, you will need to connect the module to the output device (speakers, headphones or amplifier). To do so, review the schematics and pinouts and connect as required. For most applications, you should just have to connect a supply voltage to Vbatt, ground the board and connect headphones/speakers to SPKN, SPKLP and SPKRP.
Once the device is wired up correctly, the Bluetooth module needs to be paired to your remote device (laptop, mobile phone etc.). To do so, search for a Bluetooth device with the name “BT-Speaker” and when prompted for a pairing code use “0000”.
Depending on the device you are using, you should be able to play audio directly without any further configuration.
Module pinout:
Pin No. |
Name |
I/O |
Description |
1 |
GND |
I/O |
Connect to ground |
2 |
GND |
I/O |
Connect to ground |
3 |
SPKN |
O |
Common speaker terminal |
4 |
SPKLP |
O |
Left-channel speaker output |
5 |
SPKRP |
O |
Right-channel speaker output |
6 |
GND |
I/O |
Connect to ground |
7 |
MIC |
I |
MIC positive input |
8 |
VMIC |
O |
MIC bias output |
9 |
BLED |
I |
Status LED 1 |
10 |
CHG |
I |
Li-Ion charger input |
11 |
RLED |
I |
Status LED 2 |
12 |
VBAT |
I |
Connect to Li-Ion battery positive terminal/Power Supply |
13 |
GND |
I/O |
Connect to ground |
14 |
GND |
I/O |
Connect to ground |
15 |
MFB |
I |
On/Off switch |
16 |
VOL+ |
I |
Volume up control |
17 |
VOL- |
I |
Volume down control |
18 |
RST |
I |
Reset pin |
19 |
TXD |
O |
UART output |
20 |
RXD |
I |
UART input |
21 |
FWD |
I |
Play next song |
22 |
BACK |
I |
Play previous song |
23 |
MUTE |
O |
Mute (Low for mute) |
24 |
1V8 |
O |
1.8V power output |
25 |
GND |
I/O |
Connect to ground |
26 |
GND |
I/O |
Connect to ground |
More Information
For more information, see the following documents: