WB2L Module Datasheet

WB2L is a low-power embedded Wi-Fi and Bluetooth LE module that Tuya has developed. It consists of a highly integrated RF chip (BK7231T) and several peripheral components, with an embedded Wi-Fi network protocol stack and robust library functions.

Overview

WB2L is embedded with a low-power 32-bit microcontroller unit (MCU), 2 MB flash memory, 256 KB static random-access memory (SRAM), and extensive peripherals.

WB2L 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.

Features

• Embedded low-power 32-bit CPU, which can also function as an application processor
• Clock rate: 120 MHz
• Operating voltage: 3.0 V to 3.6 V
• Peripherals: 5 GPIOs
• Wi-Fi connectivity
  • 802.11 b/g/n
  • Channels 1 to 14 at 2.4 GHz
  • Support WEP, WPA/WPA2, WPA/WPA2 PSK (AES),WPA3 security modes
  • Up to +16 dBm output power in 802.11b mode
  • EZ and AP net pairing modes for Android and iOS devices
  • Onboard PCB antenna with a gain of 1 dBi
  • Operating temperature: –40°C to +105°C
• Bluetooth LE connectivity
  • Support for Bluetooth LE 4.2
  • Maximum output power of +7 dBm
  • Onboard PCB antenna with a gain of 1 dBi

Applications

• Intelligent building
• Smart household and home appliances
• Smart socket and light
• Industrial wireless control
• Baby monitor
• Network camera
• Intelligent bus

Module interfaces

Dimensions and footprint

WB2L has one row of pins with a 2±0.1 mm pin spacing.

The WB2L dimensions (Lx Wx H) are 17.3±0.35 mm x 15±0.35 mm x 2.8±0.15 mm. The following figure shows the WB2L front and rear views.

Interface pin definition

Pin No.	Symbol	I/O type	Function
1	PWM2	I/O	Hardware PWM pin, which is connected to the P8/BT_ACTIVE/PWM2 (Pin24)
2	PWM1	I/O	Hardware PWM pin, which is connected to the P7/WIFI_ACTIVE/PWM1 (Pin23)
3	PWM0	I/O	Hardware PWM pin, which is connected to the P6/CLK13M/PWM0 (Pin22)
4	PWM5	I/O	Hardware PWM pin, which is connected to the P26/IRDA/PWM5 (Pin15)
5	PWM4	I/O	Hardware PWM pin, which is connected to the P24/LPO_CLK/PWM4 (Pin16)
6	GND	P	Ground pin
7	3V3	P	Power supply pin (3.3 V)

Test pin definition

Pin No.	Symbol	I/O type	Function
-	GND	P	Ground pin
-	RST	I	Reset pin, Default high level, pull down effective
-	U1_TXD	I/O	UART1_TX, User serial port
-	U1_RXD	I/O	UART1_RX, User serial port
-	U2_TXD	I/O	UART2_TX, LOG serial port
-	U2_RXD	I/O	UART2_RX, LOG serial port
-	F_SCK	I/O	Clock pin when data is downloaded from the flash memory, which is connected to the P20 pin on the internal IC
-	F_CSN	I/O	Command enabling pin when data is downloaded from the flash memory, which is connected to the P21 pin on the internal IC
-	F_SI	I/O	Data input pin when data is downloaded from the flash memory, which is connected to the P22 pin on the internal IC
-	F_SO	I/O	Data output pin when data is downloaded from the flash memory, which is connected to the P23 pin on the internal IC

Electrical parameters

Absolute electrical parameters

Parameter	Description	Minimum value	Maximum value	Unit
Ts	Storage temperature	-40	105	℃
VBAT	Power supply voltage	3.0	3.6	V
Static electricity voltage (human body model)	TAMB-25℃	-	2	KV
Static electricity voltage (machine model)	TAMB-25℃	-	0.5	KV

Working conditions

Parameter	Description	Minimum value	Typical value	Maximum value	Unit
Ta	Operating temperature	-40	-	105	℃
VBAT	Power supply voltage	3.0	3.3	3.6	V
VIL	I/O low-level input	-0.3	-	VCC*0.25	V
VIH	I/O high-level input	VCC*0.75	-	VCC	V
VOL	I/O low-level output	-	-	VCC*0.1	V
VoH	I/O high-level output	VCC*0.8	-	VCC	V
Imax	I/O drive current	-	-	12	mA

Current consumption during constant transmission and receiving

Working status	Mode	Rate	TX Power/ Receiving	Typical value	Maximum value	Unit
TX	11b	11Mbps	+17dBm	295	354	mA
TX	11g	54Mbps	+14dBm	266	300	mA
TX	11n	MCS7	+13dBm	260	290	mA
RX	11b	11Mbps	Constant receiving	98	100	mA
RX	11g	54Mbps	Constant receiving	98	100	mA
RX	11n	MCS7	Constant receiving	98	100	mA

Operating 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.	70	312	mA
AP	The module is in AP mode, and the Wi-Fi indicator blinks slowly.	70	364	mA
Connected	The module is connected to the network, and the Wi-Fi indicator is steady on.	40	244	mA
Disconnected	The module is disconnected from the network, and the Wi-Fi indicator is steady off.	100	232	mA

RF features

Basic RF features

Parameter	Description
Frequency band	2.412-2.484GHz
Wi-Fi standard	IEEE 802.11b/g/n(channels1-14)
Data transmission rate	11b: 1, 2, 5.5, 11 (Mbps) 11g: 6, 9, 12, 18, 24, 36, 48, 54(Mbps) 11n: HT20 MCS0-7
Antenna type	PCB antenna with a gain of 1dBi

TX performance

Performance during constant transmission.

Parameter	Minimum Value	Typical Value	Maximum Value	Unit
Average RF output power,802.11b CCK Mode 11M	-	16	-	dBm
Average RF output power,802.11g OFDM Mode 54M	-	14	-	dBm
Average RF output power,802.11n OFDM Mode MCS7	-	13	-	dBm
EVM@802.11b CCK 11Mbps Mode 17dBm	-	-23	-	dB
EVM@802.11g OFDM 54Mbps Mode 13.5dBm	-	-27	-	dB
EVM@802.11n OFDM MCS7 Mode 12dBm	-	-28	-	dB
Frequency error	-15	-	15	ppm

RX performance

RX sensitivity

Parameter	Minimum value	Typical value	Maximum value	Unit
PER<8%, RX sensitivity, 802.11b DSSS Mode 11M	-	-81	-	dBm
PER<10%, RX sensitivity, 802.11g OFDM Mode 54M	-	-72	-	dBm
PER<10%, RX sensitivity, 802.11n OFDM Mode MCS7	-	-68	-	dBm

Antenna

Antenna type

WB2L uses the PCB antenna.

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 15mm away from other metal parts.

To prevent an adverse impact on the antenna radiation performance, avoid copper or traces along the antenna area on the PCB. The following describes three antenna placement solutions:

1. Place the antenna outside the PCB frame.

2. Place the antenna along with the PCB frame without copper nearby.

3. Place the antenna in a carved area on the PCB.

   The preceding solutions 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.

Packaging Information and Production Instructions

Mechanical Dimensions

The PCB dimensions (L x Wx H) are 17.3±0.35mm (L)×15±0.35mm (W) ×0.8±0.1mm (H).

Side view

Recommended schematic encapsulation

Recommended PCB Encapsulation-Pin header

WB2L can be mounted onto a PCB by using an SMT placement machine or through-hole mounted onto the PCB through a pin header.

Recommended PCB Encapsulation-SMT

Production instructions

1. For the modules that can be packaged with the SMT or in an in-line way, you can select either of them according to the PCB design solutions of customers. If a PCB is designed to be SMT-packaged, package the module with the SMT. If a PCB is designed to be in-line-packaged, package the module in an in-line way. After being unpacked, the module must be soldered within 24 hours. Otherwise, it needs to be put into the drying cupboard where the relative humidity is not greater than 10%; or it needs to be packaged again under vacuum and the exposure time needs to be recorded (the total exposure time cannot exceed 168 hours).

   • (SMT process) SMT devices:
     • Mounter
     • SPI
     • Reflow soldering machine
     • Thermal profiler
     • Automated optical inspection (AOI) equipment
   • (Wave soldering process) Wave soldering devices
     • Wave soldering equipment
     • Wave soldering fixture
     • Constant-temperature soldering iron
     • Tin bar, tin wire, and flux
     • Thermal profiler
   • Baking devices:
     • Cabinet oven
     • Anti-electrostatic and heat-resistant trays
     • Anti-electrostatic and heat-resistant gloves

2. Storage conditions for a delivered module:

   • The moisture-proof bag must be placed in an environment where the temperature is below 40°C and the relative humidity is lower than 90%.

   • The shelf life of a dry-packaged product is 12 months from the date when the product is packaged and sealed.

   • There is a humidity indicator card (HIC) in the packaging bag.

     

3. The module needs to be baked in the following cases:

   • The packaging bag is damaged before unpacking.
   • There is no humidity indicator card (HIC) in the packaging bag.
   • After unpacking, circles of 10% and above on the HIC become pink.
   • The total exposure time has lasted for over 168 hours since unpacking.
   • More than 12 months have passed since the sealing of the bag.

4. Baking settings:

   • Temperature: 40°C and ≤ 5% RH for reel package and 125°C and ≤5% RH for tray package (please use the heat-resistant tray rather than plastic container)
   • Time: 168 hours for reel package and 12 hours for tray package
   • Alarm temperature: 50°C for reel package and 135°C for tray package
   • Production-ready temperature after natural cooling: < 36°C
   • Re-baking situation: If a module remains unused for over 168 hours after being baked, it needs to be baked again.
   • If a batch of modules is not baked within 168 hours, do not use the reflow soldering or wave soldering to solder them. Because these modules are Level-3 moisture-sensitive devices, they are very likely to get damp when exposed beyond the allowable time. In this case, if they are soldered at high temperatures, it may result in device failure or poor soldering.

5. In the whole production process, take electrostatic discharge (ESD) protective measures.

6. To guarantee the passing rate, it is recommended that you use the SPI and AOI to monitor the quality of solder paste printing and mounting.

Recommended oven temperature curve

Select a proper soldering manner according to the process. For the SMT process, please refer to the recommended oven temperature curve of reflow soldering. For the wave soldering process, please refer to the recommended oven temperature curve of wave soldering. There are some differences between the set temperatures and the actual temperatures. All the temperatures shown in this module datasheet are obtained through actual measurements.

Manner 1: SMT process (Recommended oven temperature curve of reflow soldering)

Set oven temperatures according to the following curve.

• A: Temperature axis

• B: Time axis

• C: Liquidus temperature: 217 to 220°C

• D: Ramp-up slope: 1 to 3°C/s

• E: Duration of constant temperature: 60 to 120s; the range of constant temperature: 150 to 200°C

• F: Duration above the liquidus: 50 to 70s

• G: Peak temperature: 235 to 245°C

• H: Ramp-down slope: 1 to 4°C/s

  Note: The above curve is just an example of the solder paste SAC305. For more details about other solder pastes, please refer to Recommended oven temperature curve in the solder paste specifications.

Manner 2: Wave soldering process (Oven temperature curve of wave soldering)

Set oven temperatures according to the following temperature curve of wave soldering. The peak temperature is 260°C±5°C.

Suggestions on oven temperature curve of wave soldering		Suggestions on manual soldering temperature
Preheat temperature	80 to 130 °C	Soldering temperature	360±20°C
Preheat time	75 to 100s	Soldering time	＜3s/point
Peak contact time	3 to 5s	NA	NA
Temperature of tin cylinder	260±5°C	NA	NA
Ramp-up slope	≤2°C/s	NA	NA
Ramp-down slope	≤6°C/s	NA	NA

Storage conditions

MOQ and packing information

Product model	MOQ (pcs)	Packing method	Number of modules in each reel Pack	Number of Reel Packs in Each Box
WB2L	4000	Carrier tape and reel packing	1000	4

Appendix: Statement

FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate this device.

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 device has been tested and found to comply with the limits for a Class B digital device, according to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This device generates, uses, and can radiate radio frequency energy and, if not installed and used following 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 device does cause harmful interference to radio or television reception, which can be determined by turning the device 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 device and receiver.
• Connect the device 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 device complies with FCC radiation exposure limits set forth for an uncontrolled rolled environment. This device should be installed and operated with a minimum distance of 20cm between the radiator and your body.

Important Note

This radio module must not be installed to co-locate and operating simultaneously with other radios in the host system except following FCC multi-transmitter product procedures. Additional testing and device authorization may be required to operate simultaneously with other radios.

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.

The host product manufacturer is responsible for compliance with any other FCC rules that apply to the host not covered by the modular transmitter grant of certification. The final host product still requires Part 15 Subpart B compliance testing with the modular transmitter installed.

The end-user manual shall include all required regulatory information/warnings as shown in this manual, including “This product must be installed and operated with a minimum distance of 20 cm between the radiator and user body”.

This device has got an FCC ID: 2ANDL-WB2L. The end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: 2ANDL-WB2L”.

This device is intended only for OEM integrators under the following conditions:

The antenna must be installed such that 20cm is maintained between the antenna and users, and the transmitter module may not be co-located with any other transmitter or antenna.

As long as the 2 conditions above are met, further transmitter tests 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.

Declaration of Conformity European Notice

Hereby, Hangzhou Tuya Information Technology Co., Ltd declares that this module product is in compliance with essential requirements and other relevant provisions of Directive 2014/53/EU,2011/65/EU. A copy of the Declaration of conformity can be found at https://www.tuya.com.

This product must not be disposed of as normal household waste, in accordance with the EU directive for waste electrical and electronic equipment (WEEE-2012/19/EU). Instead, it should be disposed of by returning it to the point of sale, or to a municipal recycling collection point.

The device could be used with a separation distance of 20cm to the human body.

Declaration of Conformity European notice

Hereby, Hangzhou Tuya Information Technology Co., Ltd declares that this module product is in compliance with essential requirements and other relevant provisions of Directive 2014/53/EU,2011/65/EU. A copy of the Declaration of conformity can be found at https://www.tuya.com

This product must not be disposed of as normal household waste, in accordance with EU directive for waste electrical and electronic equipment (WEEE- 2012/19/EU). Instead, it should be disposed of by returning it to the point of sale, or to a municipal recycling collection point.

The device could be used with a separation distance of 20cm to the human body.