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Compact 3.3V TTL to RS485 Expansion Board with 9–24V Power Input
The M5Stack S001 Stamp PWR485 is a compact RS485 communication expansion board designed to convert a microcontroller’s 3.3V TTL UART signals into differential signals compatible with the RS485 electrical standard. Built around the SP485EEN-L/TR transceiver, it provides a practical way to add RS485 connectivity to embedded controllers for industrial communication, sensor acquisition, and Modbus-based applications.
The board provides two parallel RS485 interface connections, allowing two external devices to share the same RS485 bus connection. Its PWR485 interface accepts 9–24V DC input and uses an onboard DC-DC converter to generate 5V for the module and connected host circuitry. The compact 20 × 23 mm footprint supports multiple integration methods, including SMT, DIP, and flying-lead installation, while the high-temperature protective shell supports reflow soldering up to 230°C.
Key Features
- SP485EEN-L/TR RS485 transceiver
- Converts 3.3V TTL UART signals to RS485 differential signals
- 3.3V input logic level
- 2 × parallel RS485 interfaces
- Supports connection of two devices on the same RS485 bus
- PWR485 interface supports 9–24V DC input
- Integrated DC-DC step-down circuit
- Provides 5V power for the module and host device
- Recommended baud rates: 9600 bps and 115200 bps
- Maximum tested baud rate: 128000 bps
- Low operating current
- Red power indicator LED
- Compact minimum-system expansion-board design
- Supports SMT mounting
- Supports DIP mounting
- Supports flying-lead integration
- High-temperature protective plastic shell
- Supports reflow soldering temperature up to 230°C
- Suitable for RS485 sensor networks and Modbus communication
- Arduino development support available
Applications
- RS485 communication interfaces
- Modbus device communication
- Industrial sensor data acquisition
- Embedded controller expansion
- Industrial automation nodes
- Building automation systems
- Distributed sensor networks
- Energy-monitoring systems
- Factory equipment communication
- Remote instrumentation
- MCU-to-RS485 conversion
- IoT gateway development
Model Size
Package Includes:
- 1 x Stamp PWR485
- 1 x HT3.96-4P female socket
- 2 x HY2.0-4P female sockets (blue + white)
- 1 x L-shaped hex key 1.5mm (compatible with M2 screws)
