| Main parameter |
Min. |
Max. |
Remark |
| Power supply（V） | 0 | 5.5 | Voltage over 5.5V will cause permanent damage to module |
| Blocking power（dBm） | - | 10 | Chances of burn is slim when modules are used in short distance |
| Operating temperature（℃） | -40 | 85 | / |
| No. |
Name |
Direction |
Function |
| 1 | GND | Input | Module ground |
| 2 | VCC | Input | Voltage range: 3.0～5.5V DC |
| 3 | AUX | Output | Used to indicate the working status of the module; wakes up the external MCU, and outputs low level during power-on self-check initialization; (can be left floating) |
| 4 | TXD | Output | TTL UART outputs, connects to external RXD input pin. |
| 5 | RXD | Input | TTL UART inputs, connects to external TXD output pin. |
| 6 | M1 | Input（weak pull-up） | Work with M0 to decide 4 working modes of module (not float, if not used, could be grounded). |
| 7 | M0 | Input（weak pull-up） | Work with M1 to decide 4 working modes of module (not float, if not used, could be grounded). |
| 11 | ANT | Output | Antenna interface (high frequency signal output, 50 ohm impedance) |
| 12 | GND | - | Fixed ground |
| 13 | GND | - | Fixed ground |
| 14 | GND | - | Fixed ground |
| 18 | NC | Input/Output | NC pin, this pin needs to be left floating (for subsequent expansion) |
| 19 | NC | Input/Output | NC pin, this pin needs to be left floating (for subsequent expansion) |
| 20 | NC | Input/Output | NC pin, this pin needs to be left floating (for subsequent expansion) |
| 21 | NC | Input | (Users do not need to connect, to be left floating) |
| 22 | NC | Input | (Users do not need to connect, to be left floating) |
| 23 | GND | Input | Fixed ground |
| 24 | NC | Input | (Users do not need to connect, to be left floating) |
