WR4 Module

WR4 is a low power embedded Wi-Fi module developed by Tuya Smart.

Scope of application

This topic describes relevant information about WR4 module during MCU connection development.

WR4 is a low power embedded Wi-Fi module developed by Tuya Smart. The module consists of a highly integrated radio-frequency identification (RFID) chip RTL8710BN and an extended flash chip, with a built-in Wi-Fi network protocol stack and various library functions. WR4 also has low-power ARM CM4F, WLAN MAC, and 1T1R WLAN. The highest basic frequency is 125 MHz. The module has 256 KB built-in static random access memory (SRAM), 2 MB flash, and numerous peripheral resources. As a real time operating system (RTOS) platform, WR4 integrates all function libraries of Wi-Fi MAC and TCP/IP protocols. You can develop your own embedded Wi-Fi products.

For more information, see WR4 Module Datasheet.

Typical application diagram

• Reference diagram of coordinated processing mode of the module and 3.3 V MCU:

  

• Reference diagram of coordinated processing mode of the module and 5 V MCU:

  

Design specification

• Module power supply:

  • When the module is in the working mode, the maximum transient current reaches 428 mA. It is recommended that the supply current of the 3.3 V module should exceed 500 mA.
  • In the PCB layout, capacitors C1 and C2 at the power input pin shall be arranged near the power supply pin. The capacitance shall exceed 10 uF.

• Module pin:

  • There are no special pins. For more information, see WR4 Module Datasheet.

• Radio frequency (RF) of the module:

  • Antenna type: the external antenna. It is recommended to use the FPC antenna shown in the figure below, or you can choose a standard antenna according to the product assembly method.

  • When a PCB onboard antenna is used in the Wi-Fi module, it is recommended that the distance between the module antenna and other metal parts should be at least 15 mm, in order to reduce the antenna interference and optimize the Wi-Fi performance.

  • The design drawing of U.FL RF connector is shown below: