Features
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FW3726 Bluetooth Module
Bluetooth® v4.2 specification compliant
Microchip’s own Bluetooth software stack for the
headset or speaker application.
It supports following profiles :
HFP/HSP/AVRCP/A2DP/SPP
20 bit DAC and 16 bit ADC codec
98dB SNR DAC playback
- Noise suppression
Microchip issc 2064s Audio Solution
Fully Qualified Single-chip
Bluetooth® v4.2 System
FW3726
V1.0
- Echo cancellation
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- SBC and optional AAC decoding
- Support both digital audio I2S format and
analog audio output
- Packet loss concealment
- Support SCMS-T
Built-in four languages ( Chinese/ English/
Spanish/ French) voice prompts
Ultra low power consumption under 15mA for
SCO/A2DP link
Analog single-end audio output
Charging current up to 350mA
Support SCMS-T
32 x 15 x 2.5 mm3 SMT package
Firmware can be field upgraded via USB
RF
2.4G Radio
UART
LEDs
PIOs
MCU
ROM/RAM
Audio in/out
Clock
Debug
Generation
eeprom
issc2064s
16MHz
General Description
FW3726 is a high performance, cost effective,
low power and compact dual mode solution.
The Bluetooth module provides a complete
2.4GHz Bluetooth system based on the
Applications

Bluetooth stereo headset

Bluetooth stereo speaker

Bluetooth stereo speaker phone

Bluetooth car audio unit
IS2064S chipset which is a single chip radio

Sound bar - subwoofer
and baseband IC for Bluetooth 2.4GHz

Multi-speaker
systems,. This module is fully compliant to
Bluetooth4.1 for audio communications
Freewings Technologies Co., Ltd
www.free-wings.cn
Features

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Fully Certified, Embedded 2.4 GHz
Bluetooth® Version 4.2 Module
Fully supports Bluetooth
BDR/EDR/BLE specification. (FW dependent).
Bluetooth SIG Certified
Onboard embedded Bluetooth Stack
Transparent UART mode for seamless serial
data over UART interface
Easy to configure with Windows GUI or direct by
MCU
Firmware can be field upgraded via USB
Compact surface mount module:
32 x 15 x 2.5 mm3
Castellated surface mount pads for easy and
reliable host PCB mounting
Environmental friendly, RoHS compliant
Perfect for Portable Battery Operated
Devices
Internal Battery Regulator Circuitry
Worldwide regulatory certifications
Support both digital audio I2S format and
analog audio output
Operating Condition:


Operating voltage: 3.2V to 4.2V
Temperature range: ‐20C to 70°C
RF/Analog:

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Peripherals
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Flexible HCI interface:
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Frequency: 2.402 to 2.480 GHz
Receive Sensitivity: ‐90 dBm (2Mbps EDR)
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Support 64 kb/s A-Law or -Law PCM format,
or CVSD (Continuous Variable Slope Delta
Modulation) for SCO channel operation.
Noise suppression
Echo suppression
SBC and optional AAC decoding
Packet loss concealment
Support SCMS-T
High speed HCI-UART (Universal Asynchronous
Receiver Transmitter) interface (up to 921600bps)
MAC/Baseband/Higher Layer:
Audio processor:

Built-in Lithium-ion and Lithium Polymer battery
charger (up to 350mA)
Integrate 3V, 1.8V configurable switching
regulator
and LDO
Built-in ADC for battery monitor and voltage
sense.
Built-in ADC for charger thermal protection.
Built-in UVP (Under voltage protection).
A aux-in port for external audio input
Two LED drivers
Integrated crystal, internal voltage regulator, and
matching circuitry
Multiple I/O pins for control and status
Secure AES128 encryption
Support BLE
- Generic Access Service
- Device Information Service
- Proprietary Services for data communication.
Bluetooth profiles
- HFP v1.6
- HSP v1.2
- A2DP v1.3
- AVRCP v1.6
- SPP v1.2
RF/Analog:


Frequency: 2.402 to 2.480 GHz
Receive Sensitivity: ‐90 dBm (2Mbps EDR)
Antenna:

High efficiency Printed Antenna.
Audio Codec:
Compliance:

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20 bit DAC and 16 bit ADC codec
98dB SNR DAC playback
FW3726 Bluetooth Audio Module Datasheet V1.0
Bluetooth SIG QDID: XXXXXX
Module certified for the United States (FCC) and
Canada (IC), European Economic Area (CE),
Page 2 of 41
BM64 is Microchip's name, FreeWings is FW3726
General Description:
Stereo module is a fully-certified
Bluetooth® Version 4.2 (BDR/EDR/BLE)
module for designers who want to add
Bluetooth® wireless audio and voice
applications to their products.
This Bluetooth SIG certified module
provides a complete wireless solution with
Bluetooth stack, integrated antenna, and
worldwide radio certifications in a compact
surface mount package. This stereo module
built-in Li-Ion charger and contain a digital
audio interface. It supports HSP, HFP, SPP,
FW3726 Bluetooth Audio Module Datasheet V1.0
A2DP, and AVRCP profiles. Both AAC and
SBC codecs are supported for A2DP. Note
that the customer must connect their own
external analog CODEC/DSP/amplifier and
MCU for audio output.
BLE support standard Generic Access Service,
Device Information Service and a proprietary
service. The proprietary service is for data
Communication.
Applications:

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Bluetooth sound bar
Bluetooth stereo speaker phone
Bluetooth stereo multi - speaker
Page 3 of 41
Contents
1 DEVICE OVERVIEW........................................................................................................................................6
2 KEY FEATURES TABLE................................................................................................................................. 9
3 INTERFACE DESCRIPTION.........................................................................................................................10
4 TRANSCEIVER................................................................................................................................................ 12
4.1 TRANSMITTER.................................................................................................................................. 12
4.2 RECEVIER...........................................................................................................................................12
4.3 SYNTHESIZER................................................................................................................................... 12
4.4 MODEM............................................................................................................................................... 12
4.5 AFH (ADAPTIVE FREQUENCY HOPPING)............................................................................................. 12
5 AUDIO................................................................................................................................................................13
5.1 DIGITAL SIGNAL PROCESSOR...................................................................................................... 13
5.2 CODEC.................................................................................................................................................14
5.3 LINE IN (AUX IN)................................................................................................................................ 17
5.4 ANALOG SPEAKER OUTPUT......................................................................................................... 18
6 POWER MANAGEMENT UNIT....................................................................................................................19
6.1 CHARGING A BATTERY..................................................................................................................19
6.2 VOLTAGE MONITORING................................................................................................................ 19
6.3 LED DRIVER.......................................................................................................................................20
6.4 UVP...................................................................................................................................................... 20
6.5 AMBIENT DETECTION (AMB_DET)..............................................................................................20
7 APPLICATION INFORMATION.................................................................................................................. 21
7.1 OPERATION WITH EXTERNAL MCU........................................................................................... 21
7.2 I2S SIGNAL APPLICATION.....................................................................................................................26
7.3 RESET (RST_N).................................................................................................................................. 27
8 ELECTRICAL CHARACTERISTICS...........................................................................................................28
9 PRINTED ANTENNA INFORMATION........................................................................................................32
9.1 MODULE RADIATION PATTERN...................................................................................................32
9.2 MODULE PLACEMENT RULE........................................................................................................ 33
10 CERTIFICATION INFORMATION............................................................................................................35
10.1 REGULATORY APPROVAL...........................................................................................................35
11 MODULE OUTLINE AND REFLOW PROFILE...................................................................................... 36
11.1 MODULE DIMENSION AND PCB FOOT PRINT.........................................................................36
11.2 REFLOW PROFILE.......................................................................................................................... 38
12 RECOMMENDED REFLOW TEMPERATURE PROFILE..................................................................... 39
13 RECORD OF CHANGES............................................................................................................................. 40
14 IMPORTANT NOTICE................................................................................................................................ 41
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 4 of 41
Abbreviations List:
HFP: Hands-free Profile
AVRCP: Audio Video Remote Control Profile
A2DP: Advanced Audio Distribution Profile
PBAP: Phone Book Access Profile
HSP: Headset Profile
SPP: Serial Port Profile
NFC: Near Field Communication
CDA: Class D Amplifier
SCMS-T: Serial Copy Management System
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 5 of 41
1 DEVICE OVERVIEW
The stereo module series include FW3726. The chip integrates Bluetooth 4.2 radio
transceiver, PMU and DSP. Below figures shows the application block diagram.
FIGURE 1‐1:Typical Application
The following depicts an example of FW3726 module connected to an MCU, external DSP/CODEC.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 6 of 41
FIGURE 1‐2: Sound bar - subwoofer Typical Application
The following depicts an example of sound bar - subwoofer connection.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 7 of 41
FIGURE 1‐4: Multi-speaker Typical Application
The following depicts an example of multi-speaker connection.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 8 of 41
2 KEY FEATURES TABLE
Chip
Feature
Application
Stereo/Mono
Pin count
Dimension (mm2)
Non-Shielding Case P/N
Non-Shielding Case P/N
PCB Antenna
BT Class of device/service field
Typical. TX Power
Audio DAC output
DAC (single-end) SNR@2.8V (dB)
DAC (cap-less) SNR@2.8V (dB)
ADC SNR @2.8V (dB)
I2S digital interface
Analog Aux- in
Mono MIC
Support external audio AMP
UART
LED Driver
Internal DC-DC step-down
DC 5V Adaptor Input
Battery Charger (350mA max)
ADC For Thermal Charger
Support UVP
GPIO for Application
Button support
Support NFC application
Build-in EEPROM
FW3726 CLASS2
Stereo
FW3726 CLASS1
Speaker/I2S Speaker
Stereo
43
43
15x32
BM64SPKS1MC2
BM64SPKA1MC2
Y
Class 2
2dBm
2-ch
-98
-96
-90
15x32
BM64SPKS1MC1
BM64SPKA1MC1
Y
Class 1
12dBm(TBD)
2-ch
-98
-96
-90
Y
Y
1
Y
Y
2
Y
Y
Y
Y
Y
12
6
Y
Y
Y
Y
1
Y
Y
2
Y
Y
Y
Y
Y
12
6
Y
Y
Customized voice prompt
EEPROM
EEPROM
Multi-tone
DSP sound effect
Profile
HFP
AVRCP
A2DP
HSP
SPP
Y
Y
1.6
1.6
1.3
1.2
Y
Y
1.6
1.6
1.3
1.2
1.2
Note: “Y” means support the feature.
1.2
“X” means no support the feature.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 9 of 41
3 INTERFACE DESCRIPTION
BM64 pin diagram is shown in Figure 3-2. The pin descriptions are shown in Table 3-2
FIGURE 3-1: FW 3726 PIN DIAGRAM
Pin No.
I/O
Name
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
I
I/O
I/O
O
O
O
O
I
I
P
I
I
I
P
I/O
DR0
RFS0
SCLK0
DT0
AOHPR
AOHPM
AOHPL
MICN1
MICP1
MICBIAS
AIR
AIL
RST_N
GND
P1_2
I2S interface: DAC Digital Left/Right Data
I2S interface: DAC Left/Right Clock
I2S interface: Bit Clock
I2S interface: ADC Digital Left/Right Data
R-channel analog headphone output
Headphone common mode output/sense input.
L-channel analog headphone output
MIC 1 mono differential analog negative input
MIC 1 mono differential analog positive input
Electric microphone biasing voltage
R-channel single-ended analog input
L-channel single-ended analog input
System Reset Pin (Low active)
Ground Pin
EEPROM clock SCL
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 10 of 41
16
17
18
I/O
I/O
I/O
P1_3
P0_4
P1_5
19
20
21
22
23
24
25
26
I
O
P
P
P
P
P
I
HCI_RXD
HCI_TXD
VDD_IO
BAT_IN
ADAP_IN
SYS_PWR
AMB_DET
PWR(MFB)
27
28
29
I
I
I/O
LED2
LED1
P3_7
30
I/O
P3_5
31
I/O
P0_0
32
I
EAN
33
34
35
I/O
I/O
I/O
DM
DP
P0_5
36
I/O
P3_0
37
I/O
P3_1
38
I/O
P3_3
39
I/O
P3_6
40
I/O
P0_2
41
I/O
P2_0
42
I/O
P2_7
43
P
GND
EEPROM data SDA
No Connection
IO pin, default pull-high input (*1)
Multi-SPK Master/Slave mode control for IS2064.
HCI-UART RX data
HCI-UART TX data
Power output , no need to add power to this pin
3.2~4.2V Li-Ion battery input
5V power adaptor input
System Power Output
ADC analog input for ambient detection.
1. Multi-Function Push Button and power on key
2. UART RX_IND, active high
LED Driver 2
LED Driver 1
IO pin, default pull-high input (*1)
UART TX_IND, active low
IO pin, default pull-low input
Slide Switch Detector, active high
IO pin, default pull-high input (*1)
Out_Ind_0
Embedded ROM/Flash enable, default pull-high
H: ROM; L: Flash
USB Data Minus data line
USB Data Positive data line
IO pin, default pull-high input (*1)
Volume down key (default)
IO pin, default pull-high input (*1)
Aux-in Detector
GIO pin, default pull-high input (*1)
REV key (default), active low
IO pin, default pull-high input (*1)
FWD key when class 2 RF, active low
IO pin, default pull-high input (*1)
Multi-SPK Master/Slave mode control.
IO pin, default pull-high input (*1)
Play/Pause key as the default setting
System Configuration, default pull-high input
H: Application L: Baseband(IBDK Mode)
IO pin, default pull-high input (*1)
Volume up key (default)
Ground Pin
* I: signal input pin
* O: signal output pin
* I/O: signal input/output pin
* P: power pin
Note:
(1) These button or functions can be setup by “IS206XGM_UI” tool.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 11 of 41
4 TRANSCEIVER
The stereo audio chip is designed and optimized for Bluetooth 2.4 GHz system. It contains a
complete radio frequency transmitter/receiver section. An internal synthesizer generates a stable
clock for synchronize with another device.
4.1
TRANSMITTER
The internal PA has a maximum output power of +4dBm with. This is applied into Class2/3 radios
without external RF PA.The transmitter directly performs IQ conversion to minimize the frequency drift.
4.2
RECEVIER
The LNA operates with TR-combined mode for single port application. It can save a pin on package
and without an external TX/RX switch.
The ADC is utilized to sample the input analog wave and convert into digital signal for de-modulator
analysis. A channel filter has been integrated into receiver channel before the ADC, which to reduce
The external component count and increase the anti-interference capability.
The image rejection filter is used to reject image frequency for low-IF architecture. This filter for lowIF architecture is intent to reduce external BPF component for super heterodyne architecture.
RSSI signal is feedback to the processor to control the RF output power to make a good tradeoff for
effective distance and current consumption.
4.3
SYNTHESIZER
A synthesizer generates a clock for radio transceiver operation. There is a VCO inside with tunable
internal LC tank. It can reduce variation for components. A crystal oscillation with internal digital
trimming circuit provides a stable clock for synthesizer.
4.4
MODEM
For Bluetooth v1.2 specification and below, 1 Mbps was the standard data rate based on Gaussian
Frequency Shift Keying (GFSK) modulation scheme. This basic rate modem meets BDR requirements
of Bluetooth v2.0 with EDR specification.
For Bluetooth v2.0 and above with EDR specification, Enhanced Data Rate (EDR) has been
introduced to provide 2 and 3 Mbps data rates as well as 1 Mbps. This enhanced data rate modem
meets EDR requirements of Bluetooth v2.0 with EDR specification. For the viewpoint of baseband,
both BDR and EDR utilize the same 1MHz symbol rate and 1.6 KHz slot rate. For BDR, 1 symbol
represents 1 bit. However each symbol in the payload part of EDR packets represents 2 or 3 bits. This
is achieved by using two different modulations, π/4 DQPSK and 8DPSK.
4.5
AFH (Adaptive Frequency Hopping)
Stereo audio chip have AFH function to avoid RF interference. It has an algorithm to check the
interference nearby and choose clear channel to transceiver Bluetooth signal.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 12 of 41
5 AUDIO
There are a few stages for input audio and output audio. Each stage can be programmed to vary
the gain response characteristics. For microphone input, both single-end input and differential input
are supported. One of the important points in maintaining a high quality signal is to provide a stable
bias voltage source to the condenser microphone’s FET. DC blocking capacitors may be used at both
positive and negative sides of input. Internally, this analog signal is converted to 16-bit 8 kHz linear
PCM data.
5.1
DIGITAL SIGNAL PROCESSOR
A digital signal processor (DSP) is used for perform speech and audio processing. Advanced
speech features are built in such as acoustic echo cancellation and noise reduction et al. To reduce
nonlinear distortion and help echo cancellation, an outgoing signal to the speaker which level exceeds
the threshold (and therefore deemed likely to create echo) will be resulting in suppression of the
signal. Adaptive filtering is also applied to track the echo path impulse response to provide echo free
and fullduplexuser experience. The embedded noise reduction algorithm helps extract clean speech
signals from the noisy inputs captured by microphones, and improves mutual understanding in
communication. Advanced audio features are built in too such as multi-band dynamic range control,
parametric multiband equalizer, audio widening and virtual bass et al. Those audio effect algorithms
are to improve users’ audio listening experience in terms of better quality after audio signal
processing.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 13 of 41
FIGURE 5-1: BLOCK DIAGRAM OF DSP
Processing flow of speakerphone applications for (a) speech and (b) audio signal
processing.
There is a “DSPTool_IS206XGM” can support user to set up these DSP parameter. For more
detail
information, please reference “BT5506_DSP_APP” document.
5.2
CODEC
The built-in codec has a high Signal to Noise ratio performance. This built-in codec consist of an
analog to digital converter (ADC), a digital to analog converter (DAC) and additional analog circuitry.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 14 of 41
FIGURE 5-2: CODEC DAC DYNAMIC RANGE
FIGURE 5-3: CODEC DAC THD+N VS. INPUT POWER
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 15 of 41
FIGURE 5-4: CODEC DAC FREQUENCY RESPONSE (CAPLESS MODE)
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 16 of 41
FIGURE 5-5: CODEC DAC FREQUENCY RESPONSE(CAPLESS MODE)
5.3
LINE IN (Aux In)
The chip supports one analog line in from external audio source. The analog line in signal can be
processed by the DSP to generate different sound effect (Multi-band Dynamic Range
Compression,
Audio Widening). The sound effect can be set up by DSP tool.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 17 of 41
5.4
ANALOG SPEAKER OUTPUT
FW3726 support two speaker output mode. One is cap-less mode which is for headphone
application, cap-less output connection is suggested to skip the large DC blocking capacitor. The
other is single-end mode which is for external audio amplifier connection and the DC blocking
capacitor needed.
FIGURE 5-6: Analog Speaker output Cap-less mode
FIGURE 5-7: Analog Speaker output Single-end mode
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 18 of 41
6 POWER MANAGEMENT UNIT
The on-chip Power management Unit (PMU) has two main feature; Lithium Ion battery charging
and voltage regulation. A power switch is used to switch over the power source between battery and
adaptor automatically. The PMU also provides driving current for 2 LEDs.
6.1
CHARGING A BATTERY
Stereo audio chip has a built-in battery charger which is optimized for lithium polymer batteries.
The charger includes a current sensor for charging control, user programmable current regulation and
high accuracy voltage regulation.
The charging current parameters are configured by “IS206XGM_UI” tool. Whenever the adaptor
is plug-in, the charging circuit will be activated. Reviving, Pre-charging, Constant Current and
Constant Voltage modes are implemented and re-charging function is also included. The maximum
charging current is 350mA.
FIGURE 6-1: CHARGING CURVE
6.2
VOLTAGE MONITORING
A 10-bit Successive-Approximation-Register analog to digital converter (SAR ADC) provides one
dedicated channel for battery voltage level detection. The warning level is programmable by
“IS206XGM_UI” tool. This ADC provides a good resolution that MCU can control the charging process.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 19 of 41
6.3
LED DRIVER
There are two or three dedicate LED drivers to control the LEDs. They provide enough sink current
(16 step control and 0.35mA for each step) that LED can be connected directly with FW3726 . LED
setting can be set up by “IS206XGM_UI” tool.
6.4
UVP
When SYS_PWR voltage is less than 2.9V, the system will be shut-down.
6.5
AMBIENT DETECTION (AMB_DET)
FW3726 built in ADC for charger thermal protection. The suggested circuit is like below and the
thermistor use Murata NCP15WF104F. The charger thermal protection could avoid battery charged in
disallowed temperature range. The temperature’s upper limit and lower limit values are configured by
“IS206XGM_UI” tool.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 20 of 41
7 APPLICATION INFORMATION
7.1
OPERATION WITH EXTERNAL MCU
Stereo module support UART command set to make an external MCU to control module.
Here is the connection interface between FW3726 and MCU.
FIGURE 7-1: INTERFACE BETWEEN MCU AND FW3726 MODULE
MCU can control module by UART interface and wakeup module by PWR pin. Stereo module
provide wakeup MCU function by connect to P0_0 pin for BM62 module and P3_7 for BM64
module.
“UART Command Set” document provide all function which module support and UI tool will help
you to set up your system support UART command.
For more detail description, please reference “UART_CommandSet” document and
“IS206XGM_UI” tool.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 21 of 41
Here are some suggestions of UART control signal timing sequence:
FIGURE 7-2: POWER ON/OFF SEQUENCE
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 22 of 41
FIGURE 7-3: TIMING SEQUENCE OF RX INDICATION AFTER POWER ON
FIGURE 7-4: TIMING SEQUENCE OF POWER OFF
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 23 of 41
FIGURE 7-5: TIMING SEQUENCE OF POWER ON (NACK)
FIGURE 7-6: RESET TIMING SEQUENCE IF MODULE HANGS UP
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 24 of 41
FIGURE 7-7: TIMING SEQUENCE OF POWER DROP PROTECTION
If BT’s BAT use adaptor translates voltage by LDO, we recommend use “Reset IC” to avoid power
off suddenly. Rest IC spec output pin must be “Open Drain”、delay time ≦ 10ms
Recommend part: TCM809SVNB713 or G691L293T73
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 25 of 41
7.2
I2S Signal Application
FW3726 support I2S digital audio signal interface to connect your external CODEC/DSP. It provide
8K,
16K, 44.1K, 48K, 88.2K and 96KHz sampling rate; it also support 16bits and 24bits data format. The
I2S setting can be set up by UI and DSP tools.
.
The external CODEC/DSP needs to be connected to SCLK0, RFS0, DR0, and DT0 (pins 3, 2, 1, and
4 respectively). The I2S signal connection between FW3726 and external DSP as below:
FIGURE 7-8: MASTER MODE REFERENCE CONNECTION
FIGURE 7-9: SLAVE MODE REFERENCE CONNECTION
About “Mast” or “Slave” mode setting, you can use “DSP Configuration Tool” to set up system.
The clock and data timing as below:
FIGURE 7-10: TIMING FOR I2S MODES (both master and slave)
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 26 of 41
FIGURE 7-11: TIMING FOR PCM MODES (both master and slave)
7.3
RESET (RST_N)
The module provides a watchdog timer to reset the chip. It has an integrated Power-On Reset (POR)
circuit that resets all circuits to a known power-on state. This action can also be driven by an external
reset signal that can be used to externally control the device, forcing it into a power-on reset state.
The RST_N signal input is active low and no connection is required in most applications.
FW3726 Bluetooth Audio Module Datasheet V1.0
Page 27 of 41
8 ELECTRICAL CHARACTERISTICS
Table 8-1: ABSOLUTE MAXIMUM SPECIFICATION
Symbol
BAT_IN
ADAP_IN
TSTORE
TOPERATION
Parameter
Input voltage for battery
Input voltage for adaptor
Storage temperature
Operation temperature
Min
Max
0
0
TBD
-20
4.3
7.0
+150
+70
Unit
V
V
ºC
ºC
Table 8-2: RECOMMENDED OPERATING CONDITION
Symbol
BAT_IN
ADAP_IN
TSTORE
Parameter
Input voltage for battery
Input voltage for adaptor
Storage temperature
Min
Typical
Max
3.2
4.5
-20
3.8
5
+25
4.2
5.5
+70
Unit
V
V
ºC
Note:
Absolute and Recommended operating condition tables reflect typical usage for device.
TABLE 8-3: I/O AND RESET LEVEL
Parameter
I/O Supply Voltage (VDD_IO)
I/O Voltage Levels
VIL input logic levels low
VIH input logic levels high
VOL output logic levels low
VOH output logic levels high
RST_N
Threshold voltage
Min.
3.0
Typ.
3.3
0
2.0
Max.
3.6
Units
V
0.8
3.6
0.4
V
V
V
V
2.4
1.6
V
Note:
(1) These parameters are characterized but not tested in manufacturing.
Table 8-4: BATTERY CHARGER
Parameter
Min
Typical
Max
Unit
ADAP_IN Input Voltage
4.5
5.0
5.5
V
Supply current to charger only
3
4.5
mA
Maximum Battery
Headroom > 0.7V
350
mA
Fast Charge Current
(ADAP_IN=5V)
Headroom = 0.3V~0.7V
175
mA
(ADAP_IN=4.5V)
Trickle Charge Voltage Threshold
3
V
Battery Charge Termination Current,
10
%
(% of Fast Charge Current)
Note:
(1) Headroom = VADAP_IN – VBAT
(2) When VADAP_IN – VBAT > 2V, the maximum fast charge current is 175mA for thermal protection.
(3) These parameters are characterized but not tested in manufacturing.
Table 8-5: LED DRIVER
Parameter
Open-drain Voltage
Programmable Current Range
Intensity Control
Current Step
Power Down Open-drain Current
Shutdown Current
Min
Typical
0
Max
3.6
5.25
16
0.35
1
1
Unit
V
mA
step
mA
μA
μA
Note:
(1) Test condition: BK_O=1.8V, temperature=25 ºC.
FW3726 Bluetooth Audio Module Datasheet V1.0
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(2) These parameters are characterized but not tested in manufacturing.
Table 8-6: AUDIO CODEC ANALOGUE TO DIGITAL CONVERTER
T= 25oC, Vdd=2.8V, 1KHz sine wave input, Bandwidth = 20Hz~20KHz
Parameter (Condition)
Resolution
Output Sample Rate
Signal to Noise Ratio (*1)
(SNR @MIC or Line-in mode)
Digital Gain
Digital Gain Resolution
MIC Boost Gain
Analog Gain
Analog Gain Resolution
Input full-scale at maximum gain (differential)
Min.
Typ.
8
Max.
16
48
Unit
Bits
KHz
dB
4.85
dB
dB
dB
dB
dB
mV
rms
mV
rms
KHz
KΩ
%
90
-54
Input full-scale at minimum gain (differential)
2~6
20
60
2.0
4
800
3dB bandwidth
20
Microphone mode (input impedance)
24
THD+N (microphone input) @30mVrms input
0.02
Note:
(1) fin=1KHz, B/W=20~20KHz, A-weighted, THD+N < 1%, 150mVpp input
(2) These parameters are characterized but not tested in manufacturing.
Table 8-7: AUDIO CODEC DIGITAL TO ANALOGUE CONVERTER
T= 25oC, Vdd=2.8V, 1KHz sine wave input, Bandwidth = 20Hz~20KHz
Parameter (Condition)
Min.
Typ.
Max.
Over-sampling rate
128
Resolution
16
20
Output Sample Rate
8
48
Signal to Noise Ratio (*1)
96
(SNR @cap-less mode) for 48kHz
Signal to Noise Ratio (*1)
98
(SNR @single-end mode) for 48kHz
Digital Gain
-54
4.85
Digital Gain Resolution
2~6
Analog Gain
-28
3
Analog Gain Resolution
1
Output Voltage Full-scale Swing (AVDD=2.8V)
495
742.5
Maximum Output Power (16Ω load)
34.5
Maximum Output Power (32Ω load)
17.2
Allowed Load
Resistive
16
O.C.
Capacitive
500
THD+N (16Ω load)(*2)
0.05
Signal to Noise Ratio (SNR @ 16Ωload)(*3)
98
Note:
(1) fin=1KHz, B/W=20~20KHz, A-weighted, THD+N < 0.01%, 0dBFS signal, Load=100KΩ
(2) fin=1KHz, B/W=20~20KHz, A-weighted, -1dBFS signal, Load=16Ω
(3) fin=1KHz, B/W=20~20KHz, A-weighted, THD+N < 0.05%, 0dBFS signal, Load=16Ω
(4) These parameters are characterized but not tested in manufacturing.
FW3726 Bluetooth Audio Module Datasheet V1.0
Unit
fs
Bits
KHz
dB
dB
dB
dB
dB
dB
mV rms
mW
mW
Ω
pF
%
dB
Page 29 of 41
Table 8-8: TRANSMITTER SECTION FOR BDR AND EDR
Parameter
Min
Typ
Max
Bluetooth
specification
< 20
-6 to 4
-4 to 1
Unit
Maximum RF
Class 1
12.0(*3)
TBD
dBm
transmit power
Class 2
2(*3)
TBD
dBm
EDR/BDR Relative transmit power
-4
-1.8
1
dB
Note:
(1) The RF TX power is modulation value.
(2) The RF Transmit power is calibrated during production using MP Tool software and MT8852
Bluetooth Test equipment.
(3) Test condition: VCC_RF= 1.28V, temperature=25 ºC.
Table 8-9: RECEIVER SECTION FOR BDR AND EDR
Modulation
Min
Sensitivity at 0.1% BER
Sensitivity at 0.01% BER
GFSK
π/4 DQPSK
8DPSK
Typ
Max
-89
-90
-83
Bluetooth
specification
≤-70
≤-70
≤-70
Unit
dBm
dBm
dBm
Note:
(1) Test condition: VCC_RF= 1.28V, temperature=25 ºC.
(2) These parameters are characterized but not tested in manufacturing.
Table 8-10: SYSTEM CURRENT CONSUMPTION OF BM62
System Status
Typ.
System Off Mode
Max.
Unit
10
uA
Stop Advertising (Samsung S5(SM-G900I) / Android 4.4.2)
Standby Mode
0.57(*1)
mA
Linked Mode
0.5(*1)
mA
eSCO Link
15.1(*1)
mA
A2DP Link
14.3(*1)
mA
Standby Mode
0.6(*1)
mA
Linked Mode
0.6(*1)
mA
SCO Link
15.3(*1)
mA
A2DP Link
15.4(*1)
mA
Stop Advertising (iPhone 6 / iOS 8.4)
Note:
(1) Based on FW DualSpeaker_v1.00_5460
(2) Mode define:
Stand Mode: Power-on without Bluetooth link.
Link Mode: With Bluetooth link in low power mode.
(4) Current consumption values are taken with
BM62 validation board as test platform.
BAT_IN= 3.8V
Distance between cell phone and EVB is 30cm
Speaker is without loading.
FW3726 Bluetooth Audio Module Datasheet V1.0
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Table 8-11: SYSTEM CURRENT CONSUMPTION OF FW3726
System Status
System Off Mode
Standby Mode
Linked Mode
SCO Link
A2DP Link
Typ.
TBD
TBD
TBD
TBD
Max.
10
Unit
uA
mA
mA
mA
mA
Note:
(1) Mode define:
Stand Mode: Power-on without Bluetooth link.
Link Mode: With Bluetooth link in low power mode.
(2) Current consumption values are taken with
FW3726 EVB board as test platform.
BAT_IN= 3.8V
Distance between cell phone and EVB is 30cm
Speaker is without loading.
FW3726 Bluetooth Audio Module Datasheet V1.0
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9 PRINTED ANTENNA INFORMATION
9.1
MODULE RADIATION PATTERN
The stereo module contains a PCB printed antenna. The PCB printed antenna radiation pattern is
shown in Figure 9-2.
FIGURE 9-1: ANTENNA KEEP OUT AREA EXAMPLES
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FIGURE 9-2: ANTENNA 3D RADIATION PATTERN @2441 MHz
9.2
MODULE PLACEMENT RULE
On the main PCB, the areas under the antenna should not contain any top, inner layer, or
bottom copper as shown in Figure 9‐1. A low‐impedance ground plane will ensure the best radio
performance (best range, lowest noise). The ground plane can be extended beyond the minimum
recommended as need for the main PCB EMC noise reduction. For the best range performance,
keep all external metal away from the ceramic chip antenna at least 15 mm.
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Here are some examples of good and poor placement on a carrier board with GND plane.
FIGURE 9-3: MODULE PLACEMENT EXAMPLES
FIGURE 9-4: GND PLANE ON MAIN APPLICATION BOARD
FW3726 Bluetooth Audio Module Datasheet V1.0
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10 CERTIFICATION INFORMATION
10.1 REGULATORY APPROVAL
FW3726 in certification test process.
• United States; FCC ID:
• Canada; IC ID:
• Europe
• Japan;
• Korea; Certification No.:
• Taiwan; NCC No.:
For more information, please reference appendix.
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11 MODULE OUTLINE AND REFLOW PROFILE
11.1 MODULE DIMENSION AND PCB FOOT PRINT
FIGURE 11-1: FW3726 Outline Dimension
PCB dimension:
X : 15.0 mm
Y : 32.0 mm
Tolerances: 0.25 mm
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FIGURE 11-2: FW3726 PCB FOOT PRINT
Note: The “Keep Out Area” is reserved for keep RF test point away from GND plane.
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11.2 REFLOW PROFILE
FIGURE 11-5: REFLOW PROFILE
Soldering Recommendations
Stereo module was assembled using standard lead ‐ free reflow profile IPC/JEDEC J ‐ STD ‐ 020.
The module can be soldered to the main PCB using standard leaded and lead‐free solder reflow
profiles. To avoid damaging of the module, the recommendations are listed as follows:
• Refer to Microchip Technology Application Note AN233 Solder Reflow
Recommendation (DS00233) for the soldering reflow recommendations
• Do not exceed peak temperature (TP) of 250 degree C
• Refer to the solder paste data sheet for specific reflow profile recommendations
• Use no‐clean flux solder paste
• Do not wash as moisture can be trapped under the shield
• Use only one flow. If the PCB requires multiple flows, apply the module on the final flow.
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12 Recommended reflow temperature profile
1) Follow: IPC/JEDEC J-STD-020 C
2) Condition:
Average ramp-up rate(217℃ to peak): 1～2℃/sec max.
Preheat: 150～200C, 60～180 seconds
Temperature maintained above 217℃: 20～40 sec
Peak temperature: 250+0/-5℃ or 260+0/-5℃
Ramp-down rate: temperature: 8 minutes max
Cycle interval: 5 minus
The module Must go through 125℃ baking for at least 9 hours before SMT
AND IR reflow process!
若拆封后未立即上线，翼动通讯建议让下次上线前务必以 125℃烘烤 9 小时以上！
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13 Record of Changes
Data
2016-04-25
Revision
V1.0
Description
Upgrade the spec. format
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14 Important Notice
Free Wings Technologies Co.,Ltd (FW) reserve the right to make changes to their products or to
discontinue any product or service without notice, and advise customers to obtain the latest version of
relevant information to verify, before placing orders, that information being relied on is current. All
products are sold subject to the FW terms and conditions of sale supplied at the time of order
acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability.
FW warrants performance of its products to specifications applicable at the time of sale in accordance
with FW’s standard warranty. Testing and other quality control techniques are utilized to the extent FW
deems necessary to support this warranty. Specific testing of all parameters of each device is not
necessarily performed, except those mandated by government requirements.
In order to minimize risks associated with customer applications, adequate design and operating
safeguards must be used by the customer to minimize inherent or procedural hazards. FW products are
not authorized for use as critical components in life support devices or systems without the express
written approval of an officer of the company. Life support devices or systems are devices or systems
that are intended for surgical implant into the body, or support or sustain life, and whose failure to
perform when properly used in accordance with instructions for use provided, can be reasonably
expected to result in a significant injury to the user. A critical component is any component of a life
support device or system whose failure to perform can be reasonably expected to cause the failure of
the life support device or system, or to affect its safety or effectiveness.
FW assumes no liability for applications assistance or customer product design. FW does not warrant or
represent that any license, either express or implied, is granted under any patent right, mask work right,
or other intellectual property right of FW covering or relating or any combination, machine, or process in
which such products or services might be or are used.
深圳地址：深圳市南山区西丽桑泰科技园 2 栋 4 楼
Address Shenzhen: 4F,2#, Sangtai Industry Park, Xili, Nanshan, Shenzhen, Guangdong Province，China,
518055
Tel: (+86 755)86116587
Fax: (+86 755)28094122
Website: www.free-wings.cn
E-mail: wenmin.zhang@free-wings.cn
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