Quectel FC908A Supplement

FC908A
Hardware Design
Wi-Fi&Bluetooth Module Series
Version: 1.0.0
Date: 2021-12-03
Status: Preliminary

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Third-Party Rights

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To implement module functionality, certain device data are uploaded to Quectel’s or third-party’s servers,
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Disclaimer
a) We acknowledge no liability for any injury or damage arising from the reliance upon the information.
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Copyright © Quectel Wireless Solutions Co., Ltd. 2021. All rights reserved.

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Safety Information
The following safety precautions must be observed during all phases of operation, such as usage, service
or repair of any cellular terminal or mobile incorporating the module. Manufacturers of the cellular terminal
shall notify users and operating personnel of the following safety information by incorporating these
guidelines into all manuals of the product. Otherwise, Quectel assumes no liability for customers’ failure to
comply with these precautions.
Full attention must be given to driving at all times in order to reduce the risk of an
accident. Using a mobile while driving (even with a handsfree kit) causes
distraction and can lead to an accident. Please comply with laws and regulations
restricting the use of wireless devices while driving.
Switch off the cellular terminal or mobile before boarding an aircraft. The operation
of wireless appliances in an aircraft is forbidden to prevent interference with
communication systems. If there is an Airplane Mode, it shall be enabled prior to
boarding an aircraft. Please consult the airline staff for more restrictions on the use
of wireless devices on an aircraft.
Wireless devices may cause interference on sensitive medical equipment, so
please be aware of the restrictions on the use of wireless devices when in
hospitals, clinics or other healthcare facilities.
Cellular terminals or mobiles operating over radio signal and cellular network
cannot be guaranteed to connect in certain conditions, such as when the mobile bill
is unpaid or the (U)SIM card is invalid. When emergency help is needed in such
conditions, use emergency call if the device supports it. In order to make or receive
a call, the cellular terminal or mobile must be switched on in a service area with
adequate cellular signal strength. In an emergency, the device with emergency call
function cannot be used as the only contact method considering network
connection cannot be guaranteed under all circumstances.
The cellular terminal or mobile contains a transceiver. When it is ON, it receives
and transmits radio frequency signals. RF interference can occur if it is used close
to TV sets, radios, computers or other electric equipment.
In locations with explosive or potentially explosive atmospheres, obey all posted
signs and turn off wireless devices such as mobile phone or other cellular
terminals. Areas with explosive or potentially explosive atmospheres include
fuelling areas, below decks on boats, fuel or chemical transfer or storage facilities,
and areas where the air contains chemicals or particles such as grain, dust or
metal powders.

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About the Document
Revision History
Version
Date
Author
Description
-
2021-12-03
Elinor WANG/Michael DU
Creation of the document
1.0.0
2021-12-03
Elinor WANG/Michael DU
Preliminary

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Contents
Safety Information...................................................................................................................................... 3
About the Document.................................................................................................................................. 4
Contents...................................................................................................................................................... 5
Table Index.................................................................................................................................................. 7
Figure Index................................................................................................................................................ 8
1Introduction......................................................................................................................................... 9
1.1. Special Mark ............................................................................................................................ 12
2Product Overview ............................................................................................................................. 13
2.1. General Description................................................................................................................. 13
2.2. Key Features............................................................................................................................ 13
2.3. Functional Diagram.................................................................................................................. 15
2.4. EVB.......................................................................................................................................... 15
3Application Interfaces ...................................................................................................................... 16
3.1. General Description................................................................................................................. 16
3.2. Pin Assignment........................................................................................................................ 17
3.3. Pin Description......................................................................................................................... 18
3.4. Power Supply........................................................................................................................... 20
3.4.1. Power Supply Pins Introduction.................................................................................... 20
3.4.2. Buck Circuit Pins Introduction....................................................................................... 22
3.5. WLAN Application Interface..................................................................................................... 23
3.5.1. SDIO Interface.............................................................................................................. 23
3.5.2. WLAN_EN..................................................................................................................... 25
3.5.3. WLAN_WAKE............................................................................................................... 25
3.5.4. Introduction of WLAN Pin Multiplexing Function.......................................................... 26
3.6. Bluetooth Application Interface................................................................................................ 27
3.6.1. UART Interface............................................................................................................. 27
3.6.2. BT_EN .......................................................................................................................... 28
3.6.3. BT_WAKE_HOST and HOST_WAKE_BT................................................................... 29
3.6.4. PCM Interface............................................................................................................... 29
3.7. Other Interfaces ....................................................................................................................... 30
3.7.1. WLAN_SLP_CLK.......................................................................................................... 30
3.7.2. XTAL_IN/OUT............................................................................................................... 31
3.7.3. GPIOs........................................................................................................................... 31
3.8. RF Antenna Interfaces............................................................................................................. 31
3.8.1. Operating Frequency.................................................................................................... 32
3.8.2. Pin Definition of RF Antenna Interface......................................................................... 32
3.8.3. Reference Design......................................................................................................... 32
3.8.4. Reference Design of RF Routing.................................................................................. 33
3.8.5. Requirements for Antenna Design ............................................................................... 35
3.8.6. RF Connector Recommendation.................................................................................. 36

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4Electrical Characteristics & Reliability........................................................................................... 38
4.1. Electrical Characteristics.......................................................................................................... 38
4.2. Digital I/O Interface Characteristics......................................................................................... 39
4.3. Power Consumption................................................................................................................. 39
4.4. RF Performance....................................................................................................................... 40
4.4.1. Conducted RF Performance of Wi-Fi........................................................................... 40
4.4.2. Conducted RF Performance of Bluetooth .................................................................... 41
4.5. ESD.......................................................................................................................................... 41
5Mechanical Information.................................................................................................................... 42
5.1. Mechanical Dimensions........................................................................................................... 42
5.2. Recommended Footprint ......................................................................................................... 44
5.3. Top and Bottom Views............................................................................................................. 45
6Storage, Manufacturing & Packaging............................................................................................. 46
6.1. Storage Conditions................................................................................................................... 46
6.2. Manufacturing and Soldering................................................................................................... 47
6.3. Packaging Specifications......................................................................................................... 49
6.3.1. Carrier Tape.................................................................................................................. 49
6.3.2. Plastic Reel................................................................................................................... 49
6.3.3. Packaging Process....................................................................................................... 50
7Appendix References....................................................................................................................... 51

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Table Index
Table 1: Special Mark.................................................................................................................................12
Table 2: Key Features................................................................................................................................ 13
Table 3: I/O Parameters Definition............................................................................................................. 18
Table 4: Pin Description.............................................................................................................................18
Table 5: Definition of Power Supply and GND Pins...................................................................................20
Table 6: Definition of Buck Circuit Pins......................................................................................................22
Table 7: Recommended Inductance Parameters......................................................................................22
Table 8: Pin Definition of SDIO Interface...................................................................................................23
Table 9: Pin Definition of WLAN_EN ......................................................................................................... 25
Table 10: Pin Definition of WLAN_WAKE..................................................................................................25
Table 11: Pin setting description................................................................................................................26
Table 12: Pin Definition of SDIO Interface.................................................................................................26
Table 13: Pin Definition of UART Interface................................................................................................27
Table 14: Pin Definition of BT_EN.............................................................................................................28
Table 15: Pin Definition of BT_WAKEUP_HOST and HOST_WAKEUP_BT............................................ 29
Table 16: Pin Definition of PCM Interface.................................................................................................. 29
Table 17: Pin Definition of WLAN_SLP_CLK Interface.............................................................................30
Table 18: WLAN_SLP_CLK parameter recommendation......................................................................... 30
Table 19: XO parameter definition............................................................................................................. 31
Table 20: Pin Definition of GPIO1/GPIO2.................................................................................................. 31
Table 21: FC908A operating frequency.....................................................................................................32
Table 22: Pin Definition of RF Antenna Interfaces..................................................................................... 32
Table 23: Antenna Cable Requirements.................................................................................................... 35
Table 24: Antenna requirements................................................................................................................ 35
Table 25: Absolute Maximum Ratings....................................................................................................... 38
Table 26: Recommended Operating Conditions........................................................................................ 38
Table 27: General DC Electrical Characteristics for 1.8 V Domain...........................................................39
Table 28: General DC Electrical Characteristics for 3.3 V Domain...........................................................39
Table 29: Current Consumption of the Module (Normal Operation).......................................................... 39
Table 30: Conducted RF Output Power at 2.4 GHz Wi-Fi......................................................................... 40
Table 31: Conducted RF Receiving Sensitivity at 2.4 GHz Wi-Fi.............................................................. 40
Table 32: Conducted RF Performance of Bluetooth.................................................................................. 41
Table 33: Electrostatic Discharge Characteristics (25 ºC, 45 % Relative Humidity)................................. 41
Table 34: Recommended Thermal Profile Parameters.............................................................................48
Table 35: Carrier Tape Dimension Table (Unit: mm)................................................................................. 49
Table 36: Plastic Reel Dimension Table (Unit: mm)..................................................................................50
Table 37: Related Documents.................................................................................................................... 51
Table 38: Terms and Abbreviations...........................................................................................................51

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Figure Index
Figure 1: Functional Diagram of FC908A ........................................................................错误!未定义书签。
Figure 2: Pin Assignment (Top View) ........................................................................................................ 17
Figure 3: VBAT Circuit................................................................................................................................21
Figure 4: Power-up Timing......................................................................................................................... 21
Figure 5: Recommended Reference Design Circuit..................................................................................22
Figure 6: WLAN Application Interface Connection....................................................................................23
Figure 7: SDIO Interface Connection.........................................................................................................24
Figure 8: Block Diagram of Bluetooth Application Interface Connection...................................................27
Figure 9: Reference Design for UART Interface Connection ....................................................................28
Figure 10: PCM Interface Connection........................................................................................................29
Figure 11: Reference Design..................................................................................................................... 33
Figure 12: Microstrip Design on a 2-layer PCB .........................................................................................33
Figure 13: Coplanar Waveguide Design on a 2-layer PCB.......................................................................33
Figure 14: Coplanar Waveguide Design on a 4-layer PCB (Layer 3 as Reference Ground).................... 34
Figure 15: Coplanar Waveguide Design on a 4-layer PCB (Layer 4 as Reference Ground).................... 34
Figure 16: Dimensions of the U.FL-R-SMT Connector (Unit: mm)............................................................36
Figure 17: Mechanicals of U.FL-LP Connectors........................................................................................ 36
Figure 18: Space Factor of Mated Connector (Unit: mm)..........................................................................37
Figure 19: Top and Side Dimensions (Top and Side View).......................................................................42
Figure 20: Bottom Dimension (Top View).................................................................................................. 43
Figure 21: Recommended Footprint (Top View)........................................................................................44
Figure 22: Top and Bottom Views of the Module.......................................................................................45
Figure 23: Recommended Reflow Soldering Thermal Profile ...................................................................47
Figure 24: Carrier Tape Dimension Drawing............................................................................................. 49
Figure 25: Plastic Reel Dimension Drawing ..............................................................................................49
Figure 26: Packaging Process................................................................................................................... 50

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1Introduction
This document defines the FC908A and describes its air interfaces and hardware interfaces which are
connected with your application.
This document can help you quickly understand module interface specifications, electrical and
mechanical details, as well as other related information of the module. Associated with application notes
and user guides, you can use FC908A to design and set up applications easily.
This equipmenthas been tested and found to comply with the limits for a Class B digital device, pursuant to
Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates, uses and can radiate radio frequency
energy and, if not installed and used in accordance with the instructions, may cause harmful interference to
radio communications. However, there is no guarantee that interference will not occur in a particular
installation.
If this equipment does cause harmful interference to radio or television reception, which can be determined
by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more
of the following measures:
-- Reorient or relocate the receiving antenna.
-- Increase the separation between the equipment and receiver.
-- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
-- Consult the dealer or an experienced radio/TV technician for help.
This device complies with FCC radiation exposure limits set forth for an uncontrolled environment. In order to
avoid the possibility of exceeding the FCC radio frequency exposure limits, human proximity to the antenna
shall not be less than 20cm (8 inches) during normal operation.
This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter.
Any changes or modifications not expressly approved by the party responsible for compliance could void
the user's authority to operate this equipment. This transmitter must not be co-located or operating in
conjunction with any other antenna or transmitter.
Important Notice to OEM integrators
1. This module is limited to OEM installation ONLY.
2. This module is limited to installation in fixed applications, according to Part 2.1091(b).
3. The separate approval is required for all other operating configurations, including portable
configurations with respect to Part 2.1093 and different antenna configurations

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4. For FCC Part 15.31 (h) and (k): The host manufacturer is responsible for additional testing to verify
compliance as a composite system. When testing the host device for compliance with Part
15 Subpart B, the host manufacturer is required to show compliance with Part 15 Subpart B while the
transmitter module(s) are installed and operating. The modules should be transmitting and the evaluation
should confirm that the module's intentional emissions are compliant (i.e. fundamental and out of band
emissions). The host manufacturer must verify that there are no additional unintentional emissions other than
what is permitted in Part 15 Subpart B or emissions are complaint with the transmitter(s) rule(s).
The Grantee will provide guidance to the host manufacturer for Part 15 B requirements if needed.
Important Note notice that any deviation(s) from the defined parameters of the antenna trace, as
described by the instructions, require that the host product manufacturer must notify to Quectel Wireless
Solutions Co., Ltd that they wish to change the antenna trace design. In this case, a Class II permissive
change application is required to be filed by the USI, or the host manufacturer can take responsibility through
the change in FCC ID (new application) procedure followed by a Class II permissive change application.
End Product Labeling
When the module is installed in the host device, the FCC/IC ID label must be visible through a window
on the final device or it must be visible when an access panel, door or cover is easily re-moved. If not, a
second label must be placed on the outside of the final device that contains the following text: “Contains FCC
ID: XMR202206FC908A”
The FCC ID can be used only when all FCC compliance requirements are met.
Antenna Installation
(1) The antenna must be installed such that 20 cm is maintained between the antenna and users,
(2) The transmitter module may not be co-located with any other transmitter or antenna.
(3) Only antennas of the same type and with equal or less gains as shown below may be used with this
module. Other types of antennas and/or higher gain antennas may require additional authorization for
operation.
(4) The max allowed antenna gain is 0.52 dBi for external antenna.
In the event that these conditions cannot be met (for example certain laptop configurations or co-location
with another transmitter), then the FCC authorization is no longer considered valid and the FCC ID/IC ID
cannot be used on the final product. In these circumstances, the OEM integrator will be responsible for
re-evaluating the end product (including the transmitter) and obtaining a separate FCC/IC authorization.
Manual Information to the End User
The OEM integrator has to be aware not to provide information to the end user regarding how to install
or remove this RF module in the user’s manual of the end product which integrates this module. The end
user manual shall include all required regulatory information/warning as show in this manual.
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation.
This device complies with ISED’s licence-exempt RSSs. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation.

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Le présent appareil est conforme aux CNR d’ ISED applicables aux appareils radio exempts de licence.
L’exploitation est autorisée aux deux conditions suivantes : (1) le dispositif ne doit pas produire de brouillage
préjudiciable, et (2) ce dispositif doit accepter tout brouillage reçu, y compris un brouillage susceptible de
provoquer un fonctionnement indésirable.
Radiation Exposure Statement:
This equipment complies with ISED radiation exposure limits set forth for an uncontrolled environment. This
equipment should be installed and operated with minimum distance 20cm between the radiator & your body.
Déclaration d'exposition aux radiations:
Cet équipement est conforme aux limites d'exposition aux rayonnements ISED établies pour un
environnement non contrôlé. Cet équipement doit être installéet utiliséavec un minimum de 20 cm de
distance entre la source de rayonnement et votre corps.
This device is intended only for OEM integrators under the following conditions: (For module device use)
1) The antenna must be installed such that 20 cm is maintained between the antenna and users, and
2) The transmitter module may not be co-located with any other transmitter or antenna.
As long as 2 conditions above are met, further transmitter test will not be required. However, the OEM
integrator is still responsible for testing their end-product for any additional compliance requirements required
with this module installed.
Cet appareil estconçu uniquement pour les intégrateurs OEM dans les conditions suivantes: (Pour utilisation
de dispositif module)
1) L'antenne doit être installée de telle sorte qu'une distance de 20 cm est respectée entre l'antenne et les
utilisateurs, et
2) Le module émetteur peut ne pas être coïmplantéavec un autre émetteur ou antenne.
Tant que les 2 conditions ci-dessus sont remplies, des essais supplémentaires sur l'émetteur ne seront pas
nécessaires. Toutefois, l'intégrateur OEM est toujours responsable des essais sur son produit final pour
toutes exigences de conformitésupplémentaires requis pour ce module installé.
IMPORTANT NOTE:
In the event that these conditions can not be met (for example certain laptop configurations or co- location
with another transmitter), then the Canada authorization is no longer considered valid and the IC ID can not
be used on the final product. In these circumstances,the OEM integrator will be responsible for re-evaluating
the end product (including the transmitter) and obtaining a separate Canada authorization.
NOTE IMPORTANTE:
Dans le cas où ces conditions ne peuvent être satisfaites (par exemple pour certaines configurations
d'ordinateur portable ou de certaines co-localisation avec un autre émetteur), l'autorisation du Canada n'est
plus considérécomme valide et l'ID IC ne peut pas être utilisésur le produit final. Dans ces circonstances,

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l'intégrateur OEM sera chargé de réévaluer le produit final (y compris l'émetteur) et l'obtention d'une
autorisation distincte au Canada.
End Product Labeling
This transmitter module is authorized only for use in device where the antenna may be installed such that 20 cm may be
maintained between the antenna and users. The final end product must be labeled in a visible area with the following:
“Contains IC: 10224A-2022FC908A”.
Plaque signalétique du produit final
Ce module émetteur est autoriséuniquement pour une utilisation dans un dispositif oùl'antenne peut être installée de telle
sorte qu'une distance de 20cm peut être maintenue entre l'antenne et les utilisateurs. Le produit final doit être étiquetédans
un endroit visible avec l'inscription suivante: "Contient des IC: 10224A-2022FC908A ".
Manual Information To the End User
The OEM integrator has to be aware not to provide information to the end user regarding how to install or remove this RF
module in the user’s manual of the end product which integrates this module. The end user manual shall include all required
regulatory information/warning as show in this manual.
Manuel d'information àl'utilisateur final
L'intégrateur OEM doit être conscient de ne pas fournir des informations àl'utilisateur final quant àla façon d'installer ou de
supprimer ce module RF dans le manuel de l'utilisateur du produit final qui intègre ce module.
Le manuel de l'utilisateur final doit inclure toutes les informations réglementaires requises et avertissements comme indiqué
dans ce manuel.
1.1. Special Mark
Table 1: Special Mark
Mark
Definition
*
Unless otherwise specified, when an asterisk (*) is used after a function, feature, interface,
pin name, AT command, or argument, it indicates that the function, feature, interface, pin,
AT command, or argument is under development and currently not supported; and the
asterisk (*) after a model indicates that the sample of such model is currently unavailable.

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2Product Overview
2.1. General Description
FC908A is a Wi-Fi and Bluetooth module with low power consumption. It is a single-die WLAN (Wireless
Local Area Network) and Bluetooth combo solution supporting IEEE 802.11b/g/n 2.4 GHz WLAN
standards and Bluetooth 5.1 standard which enables seamless integration of WLAN and Bluetooth low
energy technologies.
With a SDIO 2.0 interface for WLAN, a UART and a PCM interface for Bluetooth, FC908A can provide
WLAN and Bluetooth functions.
2.2. Key Features
The following table describes the key features of FC908A.
Table 2: Key Features
Features
Details
Power Supply
⚫VBAT power supply:
Supply voltage range: 3.0–4.8 V
Typical supply voltage: 3.6 V
⚫VDDIO power supply:
Supply voltage range: 1.71–3.63 V
Typical supply voltage: 1.8/3.3 V
⚫Module buck:
VIN_LDO_OUT/VIN_LDO: typical voltage: 1.35 V
Operating Frequency
⚫2.4 GHz WLAN: 2.412–2.462 GHz
⚫Bluetooth: 2.402–2.480 GHz
Wi-Fi Transmission Data Rates
⚫802.11b: 1 Mbps, 2 Mbps, 5.5 Mbps, 11 Mbps
⚫802.11g: 6 Mbps, 9 Mbps, 12 Mbps, 18 Mbps, 24 Mbps, 36
Mbps, 48 Mbps, 54 Mbps
⚫802.11n: HT20 (MCS0–MCS7)

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1
Within operating temperature range, the module is IEEE compliant.
Wi-Fi Transmitting Power
2.4 GHz:
⚫802.11b/11 Mbps: 16 dBm ±1.5 dBm
⚫802.11g/54 Mbps: 15 dBm ±1.5 dBm
⚫802.11n/HT20 MCS7: 14 dBm ±1.5 dBm
Wi-Fi Operation Mode
⚫AP
⚫STA
Wi-Fi Modulation
DSSS, OFDM, DBPSK, DQPSK, CCK, BPSK, QPSK, 16QAM,
64QAM
WLAN Application Interface
SDIO 2.0
Bluetooth Application Interface
UART and PCM
RF Antenna Interfaces
⚫ANT_WIFI0/BT
⚫50 Ω impedance
Physical Characteristics
⚫Size: (12.0 ±0.15) mm × (12.0 ±0.15) mm × (1.95 ±0.2) mm
⚫Package: LCC
⚫Weight: TBD
Temperature Range
⚫Operating temperature range: -30 °C to +85 °C 1
⚫Storage temperature range: -40 °C to +85 °C
RoHS
All hardware components are fully compliant with EU RoHS
directive

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2.3. Functional Diagram
FC908A supports internal crystal or external crystal.
2.4. EVB
To help customers to develop applications with FC908A, the evaluation board tools include EVB board
(FC908A-M.2 and corresponding TE-A), USB 2.0 data cable, antenna and other external devices used to
control and test the module. For details, see document [1].
NOTE

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3Application Interfaces
3.1. General Description
FC908A is equipped with 44 LCC pins. The subsequent chapters will provide a detailed introduction to the
following function, pins and interfaces of the module:
⚫Power supply
⚫WLAN application interface
⚫Bluetooth application interface
⚫RF antenna interfaces
⚫Other interfaces
-WLAN_SLP_CLK
-XTAL_IN/OUT
-GPIO

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3.2. Pin Assignment
SDIO_DATA3
PCM_SYNC
VIN_LDO
PCM_DIN
RESERVED
WLAN_SLP_CLK
PCM_DOUT
PCM_CLK
VIN_LDO_OUT
SDIO_DATA1
GND
RESERVED
WLAN_EN
WLAN_WAKE
SDIO_DATA2
15 17 18
16
19
20 21
22 13 14 12
11
10
9
7
6
8
5
4
3
2
1
23
24
25
27
28
26
29
30
31
32
33
SDIO_DATA0
SDIO_CLK
SDIO_CMD
VIO
GND
GND
RESERVED
41 39 38
40
37
36 35
34 43 42 44
BT_EN
RESERVED
GND RESERVED
GPIO2
RESERVED
BT_CTS
GPIO1
BT_TXD
BT_RTS
BT_RXD
GND
GND
ANT_WIFI0/BT
RESERVED
RESERVED
HOST_WAKE_BT
BT_WAKE_HOST
RESERVED
VBAT
XTAL_OUT
XTAL_IN
FC908A
GNDPower WLAN Bluetooth RF XTAL Other signals RESERVED GPIO
Figure 1: Pin Assignment (Top View)
1. Keep all RESERVED pins open.
2. All GND pins shall connect to the ground.
NOTE

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3.3. Pin Description
The following tables show the pin description of FC908A.
Table 3: I/O Parameters Definition
Table 4: Pin Description
Type
Description
AIO
Analog Input/Output
DI
Digital Input
DO
Digital Output
DIO
Digital Input/Output
PI
Power Input
PO
Power Output
Power Supply
Pin Name
Pin No.
I/O
Description
Comment
VBAT
9
PI
Power supply for the
module
VDDIO
22
PI
Power supply for
module’s I/O pins
VIN_LDO_OUT
21
PO
Internal buck output for
the module
VIN_LDO
23
PI
Internal buck input for
the module
GND
1, 3, 20, 31, 33, 36
WLAN Application Interface
Pin Name
Pin No.
I/O
Description
Comment
WLAN_EN
12
DI
WLAN function enable
control
VDDIO power domain.
Active high.
WLAN_WAKE
13
DO
Wake up the host by
WLAN
VDDIO power domain.

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2
SDIO_DATA2 is the function configuration pin, you can select SDIO mode or SPI mode by configuring this pin. See
chapter 3.5.4 for details.
SDIO_DATA2 2
14
DIO
SDIO data bit 2/NC
VDDIO power domain.
Supports 1-bit or 4-bit mode.
SDIO_DATA3
15
DIO
SDIO data bit 3/NC
SDIO_CMD
16
DIO
SDIO command
SDIO_CLK
17
DI
SDIO clock
SDIO_DATA0
18
DIO
SDIO data bit 0
SDIO_DATA1
19
DIO
SDIO data bit 1/IRQ
Bluetooth Application Interface
Pin Name
Pin No.
I/O
Description
Comment
BT_EN
34
DI
Bluetooth enable control
VDDIO power domain.
Active high.
If unused, pull it down.
HOST_WAKE_BT
6
DI
Host wakes up Bluetooth
VDDIO power domain.
If unused, keep them open.
BT_WAKE_HOST
7
DO
Bluetooth wakes up host
PCM_DOUT
25
DO
PCM data output
PCM_CLK
26
DI
PCM clock
PCM_DIN
27
DI
PCM data input
PCM_SYNC
28
DI
PCM data frame sync
BT_RTS
41
DO
Bluetooth UART request
to send
BT_TXD
42
DO
Bluetooth UART transmit
BT_RXD
43
DI
Bluetooth UART receive
BT_CTS
44
DI
Bluetooth UART clear to
send
RF Antenna Interfaces
Pin Name
Pin No.
I/O
Description
Comment
ANT_WIFI0/BT
2
AIO
Wi-Fi0/Bluetooth
antenna interface
50 Ω impedance.