[Chip solution]：SI4438
[Carrier frequency]：425~525MHz
[Transmit power]：30dBm
[Communication distance]：5.6km
[Product size]：38.5*24mm
[Introduction]：E30-400M30S(4438) is a hardware module (SPI) based on the SI4438 RF chip imported from Silicon Labs. It is half-duplex, integrates transceiver and receiver, transparent transmission mode, SMD type, working frequency band is 425~525MHz, transmit power 1W , suitable for a variety of environments, using the SI4438 RF chip originally imported from the American Silicon Labs company, with high receiving sensitivity, strong anti-interference, and supports the development of low power consumption. It has been widely used in various industries, and has the characteristics of stable performance, long transmission distance, penetration and diffraction ability, etc.
| Main parameters | Description | Remarks |
| Reference distance | 5.6Km | In a clear and open environment, the antenna gain is 5dBi, and the antenna height is 2.5 meters.Rate 1kbps |
| Modulation | GFSK | - |
| Communication Interface | SPI | Maximum speed up to 10Mbps |
| Encapsulation | patch | - |
| Interface | stamp hole | - |
| Dimensions | 38.5*24mm | - |
| Antenna interface | IPX, stamp holes | Equivalent impedance is about 50Ω |
| Main parameters | Minimum value | Typical value | Maximum value | Unit | Condition |
| Operating Voltage | 3.3 | 5 | 5.5 | V | ≥5.0V guaranteed output power |
| Working frequency | 425 | - | 525 | MHz | Support ISM band |
| communication level | - | 3.3 | - | V | Using 5V TTL has the risk of burning |
| emission current | 550 | 650 | 700 | mA | Instantaneous power consumption |
| receive current | - | 22 | - | mA | - |
| Sleep current | - | 2 | - | μA | Software shutdown |
| Operating temperature | -40 | - | 85 | ℃ | Industrial grade |
| Maximum transmit power | 29 | 30 | 30.5 | dBm | - |
| Receiver sensitivity | -120 | -121 | -122 | dBm | 1kbps over the air |