WBR3N Module Datasheet

Last Updated on : 2024-06-14 03:15:55download

WBR3N is a low-power embedded Wi-Fi and Bluetooth module that Tuya has developed. It consists of a highly integrated wireless RF chip (RTL8720CS), a few peripherals, an embedded Wi-Fi network protocol stack, the Bluetooth LE network protocol, and varied library functions.


WBR3N has an embedded low-power 32-bit CPU, 512-KB static random-access memory (SRAM), 4-MB flash memory, and rich peripherals. WBR3N 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.


  • Embedded low-power 32-bit CPU, which can also function as an application processor
  • The maxium clock rate: 200 MHz
  • Operating voltage: 3.0 to 3.6 V
  • Peripherals: 8 GPIOs, 1 universal asynchronous receiver/transmitter (UART), and 1 analog to digital converter (ADC)
  • Support data encryption and adopt the clipper chip NXP SE050
  • Wi-Fi connectivity
    • 802.11b/g/n 1x1 2.4 G
    • Channels 1 to 14 at 2.4 Ghz
    • Support WEP/WPA/WPA2/WPA2 PSK (AES) WPA3 security mode
    • Up to +17.5 dBm output power in 802.11b mode
    • Support STA/AP/STA+AP working modes
    • Support SmartConfig and AP network configuration manners for Android and iOS devices
    • Onboard PCB antenna with a gain of 2.5 dBi at 2.4 G
    • Operating temperature: -20 to 85℃
  • Bluetooth connectivity
    • Support Bluetooth V5.0
    • Up to the output power of +9 dbm The default output power is 7dB.
    • PCB antenna with a gain of 2.5 dBi at 2.4 G shared with Wi-Fi
    • Operating temperature: -20 to 85℃


  • 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

WBR3N has two rows of pins with a 2± 0.1 mm pin spacing. The WBR3N dimensions are 16 mm (W)×24 mm (L) ×3.0 mm (H). The diagram of dimensions of WBR3N is as below:

WBR3N Module Datasheet

Note: The general shape tolerance is ±0.35 mm, the position tolerance related to the plug-in assembly is reduced to ±0.1 mm, and the tolerance of the 0.8-mm-thick plate is ±0.1 mm.

Pin definition

WBR3N Module Datasheet

Serial number Symbol I/O type Function
1 RST I/O Reset
2 ADC AI ADC^(1)^, which corresponds to PB 3 of IC
3 EN I Enabling pin, which needs to be connected to the voltage of 3.3V in normal cases and corresponds to CHIP_EN of IC
4 PA15 I/O Common IO pin, which corresponds to PA 15 of IC
5 PA25 P Support hardware PWM and correspond to PA 25 of IC
6 PA26 I/O Support hardware PWM and correspond to PA 26 of IC
7 PA28 I/O Support hardware PWM and correspond to PA 28 of IC
8 3V3 P Power supply source (3.3V)
9 GND P Power supply reference ground
10 PA14 O Common IO pin, which corresponds to PA 14 of IC
11 L_TX O UART0_TXD, which is used for displaying the internal information of a module and corresponds to UART_TXD of IC
12 PA27 I/O Common IO pin, which corresponds to PA 27 of IC
13 PA13 I/O Support hardware PWM and correspond to PA 13 of IC
14 PA12 I/O Support hardware PWM and correspond to PA 12 of IC
15 RX/PB2 I/O UART0_RXD(2), which corresponds to PB 2 of IC
16 TX/PB1 I/O UART0_TXD(2), which corresponds to PB 1 of IC

Note: P indicates power supply pins, I/O indicates input/output pins, and AI indicates analog input pins. RST is only a reset pin of a module and cannot be used for clearing information about Wi-Fi network configuration.

  • (1): The pin can only be used as an ADC interface but cannot be used as a common IO interface. Once not used, it needs to be pulled up. As an ADC input port, the input voltage range is 0 to 1.0V.
  • (2): UART0 is a user-side serial interface pin. When a module is enabled, there is information output from the user-side serial interface pin, which can be neglected.

Electrical parameters

Absolute electrical parameters

Parameter Description Minimum value Maximum value Unit
Ts Storage temperature -20 85
VBAT Power supply voltage 3.0 3.6 V
Static electricity discharge voltage (human body model) TAMB-25℃ - 2 KV
Static electricity discharge voltage (machine model) TAMB-25℃ - 0.5 KV

Normal working conditions

Parameter Description Minimum value Typical value Maximum value Unit
Ta Operating temperature -20 - 85
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

TX and RX power consumption

Transmission and receiving at 2.4G

Working status Mode Rate Transmit power/receive Maximum value (Typical value) Unit
Transmission 11b 11 Mbps +17.5 dBm 250 mA
Transmission 11g 54 Mbps +14.5 dBm 200 mA
Transmission 11n-HT20 MCS7 +14.5 dBm 200 mA
Transmission 11n-HT40 MCS7 +13.5 dBm 162 mA
Receiving 11b 11 Mbps constantly receive 70 mA
Receiving 11g 54 Mbps constantly receive 72 mA
Receiving 11n-HT20 MCS 7 constantly receive 70 mA
Receiving 11n-HT40 MCS 7 constantly receive 73 mA

Operating current

Working mode Working status, Ta = 25°C Average value Maximum value (Typical value) Unit
Quick network connection status The module is in the fast network connection state and the Wi-Fi indicator always flashes 57 184 mA
Hotspot network configuration state The module is in the hotspot network configuration state and the Wi-Fi indicator flashes slowly 203 392 mA
Network connection state The module is connected to the network and the Wi-Fi indicator is always on 55 98 mA
Disconnected status The module is disconnected and the Wi-Fi indicator is dark 53 59 mA

RF parameters

Basic RF features

Parameter Description
Working frequency Wi-Fi: 2.412 to 2.484 GHz (channels 1 to 11 for US/CA and channels 1 to 13 for EU/CN)
Bluetooth: 2402 to 2480 MHz
Wi-Fi standard IEEE 802.11 b/g/n
Data transmission rate Wi-Fi:
  • 11b: 1, 2, 5.5, 11 (Mbps)
  • 11g: 6, 9, 12, 18, 24, 36, 48, 54 (Mbps)
  • 11n: HT2 0 MCS 0 to7, HT40 MCS 0 to 7
Bluetooth: 1M/2M
Antenna Type PCB antenna with a gain of 2.5 dBi at 2.4 G

TX performance

TX Performance at 2.4 G

Parameter Minimum value Typical value Maximum value Unit
Average RF output power, 802.11b CCK Mode, 1 Mbit/s - 17.5 - dBm
Average RF output power, 802.11g OFDM mode, 54 Mbit/s - 14.5 - dBm
Average RF output power, 802.11n HT20 mode, MCS7 - 14.5 - dBm
Average RF output power, 802.11n HT40 mode, MCS7 - 13.5 - dBm
Frequency error -10 - 10 ppm

RX performance

RX sensitivity

Parameter Minimum value Typical value Maximum value Unit
PER<8%, RX sensitivity, 802.11b CCK Mode 11M - -90 - dBm
PER<10%, RX sensitivity, 802.11g, 54 M - -77 - dBm
PER<10%, RX sensitivity, 802.11n HT20-MCS7 - -75 - dBm
PER<10%, RX sensitivity, 802.11n HT20-MCS7 - -72 - dBm


Antenna type

WBR3N uses only an onboard 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 15 mm away from other metal parts.

To ensure antenna performance, the PCB should not be routed or clad with copper in the antenna area. The main points of the layout:

  • Make sure that there is no substrate medium directly below or above the printed antenna.

  • Make sure that the area around the printed antenna is far away from the metal copper skin, so as to ensure the radiation effect of the antenna to the greatest extent.

    WBR3N Module Datasheet

For the antenna area of the PCB of the module, refer to the diagram of Mechanical Dimensions.

Packaging information and production instructions

Mechanical dimensions

As shown in the following figure, the mechanical dimensions of the PCB of WBR3N are 16±0.35 mm (W)×24±0.35 mm (L) ×0.8±0.1 mm (H).

WBR3N Module Datasheet

Note: The default dimensional tolerance is ±0.35 mm. If you have specific requirements on dimensions, make them clear in the datasheet after communication.

Recommended PCB layout

The following figure is a schematic diagram of WBR3N which shows how pins correspond to each other.

WBR3N Module Datasheet

WBR3N PCB Layout is shown as below:

WBR3N Module Datasheet

Power-on sequence and resetting

Power-on sequence

The RTL8720CS chip has requirements on the power-on sequence. It is recommended that the voltage rise from 0 to 3.3V within 40mS
WBR3N Module Datasheet

Symbol Parameter Minimum value Typical value Maximum value Unit
TPRDY 3.3V ready time 0.6 40 mS
CHIP_EN CHIP_EN ready time 0.6 40 mS

Treatment of GPIO pins

A few pins (PA 12, PA 13, PA 15, PA 25, PA 28, and PA 26) of the module will have instantaneous high-level pulses before the chip fully works, and everything will be normal after the chip works. For these pins, if they are directly used as driving light sources or relays, in order to avoid the effect of burrs at the moment of power-on, refer to the following processing methods: Pull down a 1-KΩ resistor at an output port of a pin, and then connect a diode in series.

At this time, the voltage of a GPIO will drop to about 2.7V after passing through the diode. The red box represents the original drive tube on the customer’s baseboard. A diode D1 and pull-down 1-KΩ resistor need to be added. If a lamp is directly driven, pull down a 10-KΩ resistor on the grid of the positive Mos. If a lamp is not directly driven and a PWM signal will not be sent until the module is officially launched, there is no need to add a pull-down resistor and diode. If a relay is driven, you can change the diode to a resistor of 0 Ω according to the actual situation.

WBR3N Module Datasheet

Production instructions

  • The stamp-hole module must be mounted by the SMT machine. After being unpacked, it must be soldered within 24 hours. Otherwise, it must be put into the drying cupboard where the RH is not greater than 10%, or it needs to be packaged under vacuum again and the exposure time needs to be recorded (the total exposure time cannot exceed 168 hours).

    • SMT equipment:
      • Mounter
      • SPI
      • Reflow soldering machine
      • Oven temperature tester
      • Automated optical inspection (AOI) equipment
    • Baking equipment:
      • Cabinet oven
      • Anti-static heat-resistant pallets
      • Anti-static heat-resistant gloves
  • Storage conditions for a delivered module are as follows:

    • 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.
    • The package contains a humidity indicator card (HIC).
      WBR3N Module Datasheet
  • The module needs to be baked in the following cases:

    • Vacuum packing bag was found to be damaged before being unpacked.
    • There is no humidity indicator card (HIC) in the vacuum packing bag.
    • After being unpacked, 10% and above circles on the HIC become pink.
    • The total exposure time has been more than 168 hours since unpacking.
    • More than 12 months have passed since the sealing date of the bag.
  • 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 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.
  • In the whole production process, take electrostatic discharge (ESD) protective measures.

  • 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

Perform mounting with the SMT based on the following reflow oven temperature curve. The highest temperature is 245°C. The reflow temperature curve is as below:

WBR3N Module Datasheet

  • 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.

Storage conditions

WBR3N Module Datasheet

MOQ and packaging information

Product model MOQ (pcs) Shipping packaging method Number of modules per reel Number of reels per carton
WBR3N 3600 Tape reel 900 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 to 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 operate 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-WBR3N. The end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: 2ANDL-WBR3N”.

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

WBR3N Module Datasheet

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.

WBR3N Module Datasheet

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.