TUYA WB2S User manual

WB2S Datasheet
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1 Product Overview
WB2S is a low-power embedded Wi-Fi module that Tuya has developed. It consists of a
highly integrated RF chip (BK7231D) and several peripheral components, with an
embedded Wi-Fi network protocol stack and robust library functions. WB2S also
contains a low-power Arm Cortex-M4 microcontroller unit (MCU), 1T1R WLAN module,
256 KB static random-access memory (SRAM), 2 MB flash memory, and extensive
peripherals.
WB2S is an RTOS platform that integrates all function libraries of the Wi-Fi MAC and
TCP/IP protocols. You can develop embedded Wi-Fi products as required.
1.1 Features
 Embedded low-power 32-bit CPU, which can also function as an application
processor
 Clock rate: 120 MHz
 Working voltage: 3.0 V to 3.6 V
 Peripherals: five GPIOs, one universal asynchronous receiver/transmitter (UART),
and one analog-to-digital converter (ADC)
 Wi-Fi connectivity
 802.11b/g/n20/n40
 Channels 1 to 14 at 2.4 GHz
 WPA and WPA2 security modes
 Up to +16 dBm output power in 802.11b mode
 EZ net pairing mode for Android and iOS devices
 Onboard PCB antenna
Tuya WB2S Wi-Fi Module
Version: 1.0.0 Date: 2019-11-23
No.: 0000000001
Product
Manual
Global Intelligent Platform

WB2S Datasheet
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 Certified by CE and FCC
 Working temperature: –20°C to +85°C
 BT
 Support Bluetooth (V4.0)
 Maximum output power + 7dBm EIRP
 Onboard PCB antenna with a gain of -1 dBi
1.2 Application Scenarios
 Intelligent building
 Smart household and home appliances
 Healthcare
 Industrial wireless control
 Baby monitor
 Network camera
 Intelligent bus
Change History
No. Date Change Description Version After Change
1 2019-11-23 This is the first release. 1.0.0

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Contents
1 Product Overview ............................................................................................................. 1
1.1 Features .................................................................................................................. 1
1.2 Application Scenarios ............................................................................................. 2
2 Module Interfaces ............................................................................................................. 6
2.1 Dimensions and Footprint ...................................................................................... 6
2.2 Interface Pin Definition ........................................................................................... 6
3 Electrical Parameters ........................................................................................................ 7
3.1 Absolute Electrical Parameters .............................................................................. 7
3.2 Working Conditions ................................................................................................ 8
3.3 TX Current Consumption ........................................................................................ 9
3.4 RX Current Consumption ....................................................................................... 9
3.5 Working Current ..................................................................................................... 9
4 RF Features .................................................................................................................... 10
4.1 Basic RF Features ................................................................................................ 10
4.2 WB2S TX Power ................................................................................................... 11
4.3 WB2S RX Sensitivity ............................................................................................ 11
5 Antenna Information ........................................................................................................ 12
5.1 Antenna Type ........................................................................................................ 12
5.2 Antenna Interference Reduction ........................................................................... 12
5.3 Antenna Connector Specifications ....................................................................... 13
6 Packaging Information and Production Instructions ....................................................... 13
6.1 Mechanical Dimensions ....................................................................................... 13
6.2 Recommended PCB Layout ................................................................................. 14
6.3 Production Instructions ......................................................................................... 14
6.4 Recommended Oven Temperature Curve ........................................................... 16
6.5 Storage Conditions ............................................................................................... 17

WB2S Datasheet
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7. Reference Circuit ........................................................................................................... 18
7.1 Schematic Diagram .............................................................................................. 18
8 MOQ and Packing Information ....................................................................................... 19

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Figures
Figure 2-1 WB2S front and rear views ................................................................................ 6
Figure 5-1 Antenna clearance part .................................................................................... 12
Figure 6-1 WB2S mechanical dimensions ........................................................................ 13
Figure 6-2 WB2S pins ........................................................................................................ 14
Figure 6-3 Top and bottom views of the PCB to which WB2S applies .............................. 14
Figure 6-4 HIC for WB2S ................................................................................................... 15
Figure 6-5 Oven temperature curve .................................................................................. 16
Figure 7-1 WB2S schematic diagram ................................................................................ 18
Tables
Table 2-1 WB2S interface pins ............................................................................................ 6
Table 3-1 Absolute electrical parameters ............................................................................ 7
Table 3-2 Normal working conditions ................................................................................... 8
Table 3-3 Current consumption during constant transmission ............................................ 9
Table 3-4 Current consumption during constant receiving .................................................. 9
Table 3-5 WB2S working current ......................................................................................... 9
Table 4-1 Basic RF features .............................................................................................. 10
Table 4-2 Power during constant transmission.................................................................. 11
Table 4-3 RX sensitivity ..................................................................................................... 11
Table 8-1 Packing information ........................................................................................... 19

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2 Module Interfaces
2.1 Dimensions and Footprint
WB2S has two rows of pins with a 2 mm pin spacing.
The WB2S dimensions (H x W x D) are 3.3 mm x 15 mm x 18 mm. Figure 2-1 shows the
WB2S front and rear views.
Figure 2-1 WB2S front and rear views
Note:
The default dimensional tolerance is ±0.35 mm, and the tolerance for some
measurements is ±0.1 mm. The PCB thickness is 1.0±0.1 mm.
2.2 Interface Pin Definition
Table 2-1 WB2S interface pins
Pin No. Symbol I/O Type Function
1 VBAT P Power supply pin (3.3 V), which is connected to
the VBAT pin on the internal IC
2 PWM2 I/O Common GPIO, which is connected to the P8 pin
on the internal IC
3 GND P Power supply reference ground pin
4 PWM1 I/O Common GPIO, which is connected to the P7 pin
on the internal IC

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Pin No. Symbol I/O Type Function
5 RX I/O
UART1_RXD, which is used as a user-side serial
interface pin and is connected to the P10 pin on
the internal IC
6 PWM0 I/O Common GPIO, which is connected to the P6 pin
on the internal IC
7 TX I/O
UART1_TXD, which is used as a user-side serial
interface pin and is connected to the P11 pin on
the internal IC
8 AD AI ADC pin, which is connected to the P23 pin on
the internal IC
9 PWM4 I/O Common GPIO, which is connected to the P24
pin on the internal IC
10 CEN I/O
External enabled reset pin, which is active at a
low level and is connected to the CEN pin on the
internal IC
11 PWM5 I/O Common GPIO, which is connected to the P26
pin on the internal IC
Note:
P indicates a power supply pin, I/O indicates an input/output pin, and AI indicates an
analog input pin.
3 Electrical Parameters
3.1 Absolute Electrical Parameters
Table 3-1 Absolute electrical parameters
Parameter Description Minimum
Value
Maximum
Value
Unit
Ts Storage
temperature –20 85 °C
VCC Power supply
voltage –0.3 3.6 V

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Parameter Description Minimum
Value
Maximum
Value
Unit
Static electricity voltage
(human body model) Tamb = 25°C N/A 2 kV
Static electricity voltage
(machine model) Tamb = 25°C N/A 0.5 kV
3.2 Working Conditions
Table 3-2 Normal working conditions
Parameter Description Minimum
Value
Typical
Value
Maximum
Value
Unit
Ta Working
temperature –20 N/A 85 °C
VCC
Power
supply
voltage
3.0 3.3 3.6 V
VIL I/O low-level
input –0.3 N/A VCC x 0.25 V
VIH
I/O
high-level
input
VCC x 0.75 N/A VCC V
VOL I/O low-level
output N/A N/A VCC x 0.1 V
VOH
I/O
high-level
output
VCC x 0.8 N/A VCC V
Imax I/O drive
current N/A N/A 12 mA
Cpad Input pin
capacitance N/A 2 N/A pF

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3.3 TX Current Consumption
Table 3-3 Current consumption during constant transmission
Symbol Mode Power Typical Value Unit
IRF 802.11b
11 Mbit/s
16 dBm 222 mA
IRF 15 dBm 215 mA
IRF 802.11g
54 Mbit/s
15 dBm 210 mA
IRF 14 dBm 195 mA
IRF 802.11n BW20
MCS7
13 dBm 200 mA
IRF 12 dBm 185 mA
IRF 802.11n BW40
MCS7
12 dBm 190 mA
IRF 11 dBm 190 mA
3.4 RX Current Consumption
Table 3-4 Current consumption during constant receiving
Symbol Mode Typical Value Unit
IRF CPU sleep 50 mA
IRF CPU active 95 mA
3.5 Working Current
Table 3-5 WB2S working current
Working
Mode
Working Status (Ta = 25°C) Average
Value
Maximum
Value
Unit
EZ The module is in EZ mode, and
the Wi-Fi indicator blinks quickly. 100 170 mA
AP The module is in AP mode, and 50 125 mA

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Working
Mode
Working Status (Ta = 25°C) Average
Value
Maximum
Value
Unit
the Wi-Fi indicator blinks slowly.
Connected
The module is connected to the
network, and the Wi-Fi indicator is
steady on.
40 180 mA
Disconnected
The module is disconnected from
the network, and the Wi-Fi
indicator is steady off.
60 110 mA
4 RF Features
4.1 Basic RF Features
Table 4-1 Basic RF features
Parameter Description
Frequency band BT:2.400 GHz to 2.4835 GHz
WIFI:2.412 GHz to 2.484 GHz
Wi-Fi standard IEEE 802.11b/g/n (channels 1 to 14，Ch1-11 for
US/CA,Ch1-13 for EU/CN)
BT standard BT 4.0
Data transmission rate
802.11b: 1, 2, 5.5, or 11 (Mbit/s)
802.11g: 6, 9, 12, 18, 24, 36, 48, or 54 (Mbit/s)
802.11n: HT20 MCS0 to MCS7
802.11n: HT40 MCS0 to MCS7
Antenna type PCB antenna with a gain of -1.0 dBi

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4.2 WB2S TX Power
Table 4-2 Power during constant transmission
Parameter Minimum
Value
Typical
Value
Maximum
Value
Unit
Average RF output
power, 802.11b CCK
mode
1 Mbit/s N/A 16 N/A dBm
Average RF output
power, 802.11g
OFDM mode
54 Mbit/s N/A 14 N/A dBm
Average RF output
power, 802.11n
OFDM mode
MCS7 N/A 12 N/A dBm
Frequency error –2 N/A +2 ppm
EVM under 802.11b CCK, 11 Mbit/s,
16 dBm –23 dB
EVM under 802.11g OFDM, 54
Mbit/s, 14.0 dBm –27 dB
EVM under 802.11n OFDM, MCS7,
13 dBm –28 dB
4.3 WB2S RX Sensitivity
Table 4-3 RX sensitivity
Parameter Minimum
Value
Typical
Value
Maximum
Value Unit
PER < 8%, 802.11b CCK
mode 1 Mbit/s N/A –91 N/A dBm
PER < 10%, 802.11g
OFDM mode 54 Mbit/s N/A –75 N/A dBm
PER < 10%, 802.11n MCS7 N/A –68 N/A dBm

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OFDM mode
5 Antenna Information
5.1 Antenna Type
WB2S uses an onboard PCB antenna.
5.2 Antenna Interference Reduction
To ensure optimal Wi-Fi performance when the Wi-Fi module uses an onboard PCB
antenna, it is recommended that the antenna be at least 15 mm away from other metal
parts.
To prevent adverse impact on the antenna radiation performance, avoid copper or traces
along the antenna area on the PCB. Ensure that there are no substrate media above or
below the antenna and that copper is at a certain distance away from the antenna to
maximize the antenna radiation performance.
Figure 5-1 Antenna clearance part

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For details about the onboard PCB antenna area on WB2S, see Figure 6-1.
Note:
The default dimensional tolerance is ±0.35 mm. If a customer has other requirements,
clearly specify them in the datasheet after communication.
5.3 Antenna Connector Specifications
WB2S does not use an antenna connector.
6 Packaging Information and Production Instructions
6.1 Mechanical Dimensions
Figure 6-1 WB2S mechanical dimensions

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Note:
The default dimensional tolerance is ±0.35 mm. If a customer has other requirements,
clearly specify them in the datasheet after communication.
6.2 Recommended PCB Layout
Figure 6-2 WB2S pins
Figure 6-3 Top and bottom views of the PCB to which WB2S applies
6.3 Production Instructions
1. Use an SMT placement machine to mount the stamp hole module that Tuya
produces onto the PCB within 24 hours after the module is unpacked and the
firmware is burned. If not, vacuum pack the module again. Bake the module before
mounting it onto the PCB.
(1) SMT placement equipment
i. Reflow soldering machine

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ii. Automated optical inspection (AOI) equipment
iii. Nozzle with a 6 mm to 8 mm diameter
(2) Baking equipment
i. Cabinet oven
ii. Anti-static heat-resistant trays
iii. Anti-static heat-resistant gloves
2. Storage conditions for a delivered module are as follows:
(1) The moisture-proof bag is placed in an environment where the temperature is
below 30°C and the relative humidity is lower than 85%.
(2) The shelf life of a dry-packaged product is 12 months from the date when the
product is packaged and sealed.
(3) The package contains a humidity indicator card (HIC).
Figure 6-4 HIC for WB2S
3. Bake a module based on HIC status as follows when you unpack the module
package:
(1) If the 30%, 40%, and 50% circles are blue, bake the module for 2 consecutive
hours.
(2) If the 30% circle is pink, bake the module for 4 consecutive hours.
(3) If the 30% and 40% circles are pink, bake the module for 6 consecutive hours.
(4) If the 30%, 40%, and 50% circles are pink, bake the module for 12 consecutive
hours.
4. Baking settings:
(1) Baking temperature: 125±5°C
(2) Alarm temperature: 130°C

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(3) SMT placement ready temperature after natural cooling: < 36°C
(4) Number of drying times: 1
(5) Rebaking condition: The module is not soldered within 12 hours after baking.
5. Do not use SMT to process modules that have been unpacked for over three months.
Electroless nickel immersion gold (ENIG) is used for the PCBs. If the solder pads
are exposed to the air for over three months, they will be oxidized severely and dry
joints or solder skips may occur. Tuya is not liable for such problems and
consequences.
6. Before SMT placement, take electrostatic discharge (ESD) protective measures.
7. To reduce the reflow defect rate, draw 10% of the products for visual inspection and
AOI before first SMT placement to determine a proper oven temperature and
component placement method. Draw 5 to 10 modules every hour from subsequent
batches for visual inspection and AOI.
6.4 Recommended Oven Temperature Curve
Perform SMT placement based on the following reflow oven temperature curve. The
highest temperature is 245°C.
Based on the IPC/JEDEC standard, perform reflow soldering on a module at most twice.
Figure 6-5 Oven temperature curve

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6.5 Storage Conditions

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7. Reference Circuit
7.1 Schematic Diagram
Figure 7-1 WB2S schematic diagram

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8 MOQ and Packing Information
Table 8-1 Packing information
MOQ and packing information
Product
Model MOQ Packing Method
Number of
Modules in Each
Reel Pack
Number of Reel
Packs in Each
Box
WB2S 4000 Carrier tape and
reel packing 1000 4

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Appendix: Statement
Federal Communications Commission (FCC) Declaration of Conformity
FCC Caution: Any changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate this equipment.
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.
Note: This equipment has 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.
Radiation Exposure Statement
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled
rolled environment. This equipment should be installed and operated with minimum
distance 20cm between the radiator and your body.
Important Note
This radio module must not installed to co-locate and operating simultaneously with
other radios in host system except in accordance with FCC multi-transmitter product
procedures. Additional testing and equipment authorization may be required to operating
simultaneously with other radio.
The availability of some specific channels and/or operational frequency bands are
country dependent and are firmware programmed at the factory to match the intended
destination. The firmware setting is not accessible by the end user.