WR3L is a low power-consuming built-in Wi-Fi module developed by Hangzhou Tuya Information Technology Co., Ltd. It consists of a highly integrated radio frequency chip (RTL8710BX) and an external flash chip, with a built-in Wi-Fi network protocol stack and robust library functions. WR3L also contains a low power-consuming ARM CM4F, a WLAN MAC, a 1T1R WLAN, and the maximum basic frequency of 125 MHz, and is embedded with a 256 KB SRAM, a 2 MB flash, and robust peripheral resources.
WR3L is an RTOS platform that integrates all the function libraries of the Wi-Fi MAC and TCP/IP protocols. You can develop built-in Wi-Fi products as required.
Figure 1.1 shows the schematic diagram of WR3L.
Built-in low power-consuming 32-bit CPU functioning as an application processor
Working voltage: 3 V to 3.6 V
Peripherals: seven GPIOs, two UARTs, and one ADC
Wi-Fi connectivity
WR3L provides two rows of pins (2 x 8) with the distance of 2 mm between every two pins.
WR3L dimensions: 16 mm (W) x 24 mm (L) x 3.3 mm (H) (see the following figure)
Table 2.1 describes the common pins.
| No. | Symbol | I/O Type | Function |
|---|---|---|---|
| 1 | NC | / | Disconnected to be compatible with other modules |
| 2 | GPIOA_22 | I/O | GPIOA_22 |
| 3 | CHIP_EN | I/O | The pin function is disabled by firmware, user can choose not to connect. |
| 4 | GPIOA_19 | I/O | GPIOA_19 |
| 5 | GPIOA_14 | I/O | GPIOA_14, used for hardware PWM |
| 6 | GPIOA_15 | I/O | GPIOA_15, used for hardware PWM |
| 7 | GPIOA_0 | I/O | GPIOA_0, which cannot be pulled up during power-on and can be configured after power-on. It is used for hardware PWM. |
| 8 | VD33 | P | Module power supply pin (3.3 V) |
| 9 | GND | P | Power supply reference ground pin |
| 10 | ADC | AI | ADC port, with the maximum input voltage of 5 V |
| 11 | GPIOA_29 | I/O | UART_Log_RXD (used for printing the internal information of the module) |
| 12 | GPIOA_30 | I/O | UART_Log_TXD (used for printing the internal information of the module) |
| 13 | GPIOA_5 | I/O | GPIOA_5, used for hardware PWM |
| 14 | GPIOA_12 | I/O | GPIOA_12, used for hardware PWM |
| 15 | RXD | I/O | UART0_RXD (user’s serial port) |
| 16 | TXD | I/O | UART0_TXD (user’s serial port) |
Note: P indicates power-supply pins, I/O indicates input/output pins, and AI indicates analog input pins.
Table 3.1 Absolute parameters
| Parameter | Description | Minimum Value | Maximum Value | Unit |
|---|---|---|---|---|
| Ts | Storage temperature | –40 | 125 | °C |
| VDD | Power-supply voltage | –0.3 | 3.6 | V |
| Static electricity voltage (human model) | TAMB – 25°C | - | 2 | kV |
| Static electricity voltage (machine model) | TAMB – 25°C | - | 0.5 | kV |
Table 3.2 Normal electrical conditions
| Parameter | Description | Minimum Value | Typical Value | Maximum Value | Unit |
|---|---|---|---|---|---|
| Ta | Working temperature | –20 | - | 105 | °C |
| VDD | Working voltage | 3.0 | - | 3.6 | V |
| VIL | I/O low-level input | –0.3 | - | VDD x 0.25 | V |
| VIH | I/O high-level input | VDD x 0.75 | - | 3.6 | V |
| VOL | I/O low-level output | - | - | VDD x 0.1 | V |
| VOH | I/O high-level output | VDD x 0.8 | - | VDD | V |
| Imax | I/O drive current | - | - | 16 | mA |
| Cpad | Input pin capacitance | - | 2 | - | pF |
Table 3.3 TX power during constant emission
| Symbol | Mode | Rate | Typical Value | Unit |
|---|---|---|---|---|
| IRF | 11b 11 Mbit/s | 17 dBm | 287 | mA |
| IRF | 11b 11 Mbit/s | 18 dBm | 295 | mA |
| IRF | 11g 54 Mbit/s | 15 dBm | 255 | mA |
| IRF | 11g 54 Mbit/s | 17.5 dBm | 267 | mA |
| IRF | 11n BW20 MCS7 | 13 dBm | 244 | mA |
| IRF | 11n BW20 MCS7 | 16.5 dBm | 257 | mA |
| IRF | 11n BW40 MCS7 | 13 dBm | 220 | mA |
| IRF | 11n BW40 MCS7 | 16.5 dBm | 230 | mA |
Table 3.4 RX power during constant receiving
| Symbol | Mode | Typical Value | Unit |
|---|---|---|---|
| IRF | CPU sleep | 90 | mA |
| IRF | CPU active | 120 | mA |
Table 3.5 Module working current
| Working Mode | Working Status (Ta = 25°C) | Typical Value | Maximum Value | Unit |
|---|---|---|---|---|
| EZ mode | The module is in the EZ state and the Wi-Fi indicator fast flashes. | 115 | 125 | mA |
| Idle mode | The module is in the connected state and the Wi-Fi indicator is steady on. | 60 | 209 | mA |
| Working mode | The module is in the connected state and the Wi-Fi indicator is steady on. | 118 | 198 | mA |
| Disconnection mode | The module is in the disconnected state and the Wi-Fi indicator is steady off. | 34 | 192 | mA |
Note: The peak duration is about 5 µs.
The preceding parameter values vary depending on the firmware functions.
Table 4.1 Basic RF features
| Parameter | Description |
|---|---|
| Frequency band | 2.400 GHz to 2.4835 GHz |
| Wi-Fi standard | IEEE 802.11b/g/n (channels 1 to 14) |
| Data transmission rate | 11b: 1, 2, 5.5, 11 (Mbit/s) 11g: 6, 9, 12, 18, 24, 36, 48, 54 (Mbit/s) 11n: HT20 MCS0 to MCS7 11n: HT40 MCS0 to MCS7 |
| Antenna type | Onboard PCB antenna |
Table 4.2 TX power during constant emission
| Parameter | Minimum Value | Typical Value | Maximum Value | Unit | |
|---|---|---|---|---|---|
| RF average output power, 802.11b CCK mode | 11 Mbit/s | - | 17.5 | - | dBm |
| RF average output power, 802.11g OFDM mode | 54 Mbit/s | - | 14.5 | - | dBm |
| RF average output power, 802.11n OFDM mode | MCS7 | - | 13.5 | - | dBm |
| Frequency error | –20 | - | 20 | ppm |
Table 4.3 RX sensitivity
| Parameter | Minimum Value | Typical Value | Maximum Value | Unit | |
|---|---|---|---|---|---|
| PER < 8%, RX sensitivity, 802.11b CCK mode | 11 Mbit/s | - | –91 | - | dBm |
| PER < 10%, RX sensitivity, 802.11g OFDM mode | 54 Mbit/s | - | –75 | - | dBm |
| PER < 10%, RX sensitivity, 802.11n OFDM mode | MCS7 | - | –72 | - | dBm |
Only the onboard PCB antenna is used.
When using an onboard PCB antenna on a Wi-Fi module, make sure that the antenna on the module is at least 15 mm away from other metal parts to ensure optimal wireless performance.
Figure 6.1 Module dimensions
Figure 6.2 Side view
Figure 6.3 Pin mapping
Figure 6.4 Module PBC Encapsulation
WR3L provides models with and without pin headers, respectively, which can be used as required.
The following figure shows the pin header dimensions and recommended layout (unit: mm).
Storage conditions of a delivered module are as follows:
The anti-moisture bag must be placed in an environment where the temperature is under 30°C and the relative humidity is under 85%.
The shelf life of a dry-packaged product is six months from the date when the product is packaged and sealed.
Note:
Throughout the production process, each involved operator must wear an electrostatic ring.
During the operation, strictly protect the module from water and strains.
