Resources:
Wiki: www.waveshare.com/wiki/TTL_TO_RS422_(B)
Galvanically Isolated TTL to RS422 Converter with Surge Protection and DIN-Rail Mounting
The Waveshare TTL TO RS422 (B) is an industrial rail-mount serial converter designed to convert single-ended TTL signals into balanced differential RS422 signals for more reliable long-distance communication. It supports 3.3V to 5V TTL logic and full-duplex RS422 communication, making it suitable for connecting microcontrollers, embedded controllers, industrial equipment, and other TTL devices to RS422 communication networks.
The converter integrates power-supply isolation and digital signal isolation to electrically separate the TTL and RS422 sides, helping improve noise immunity in industrial environments. Protection circuitry includes a TVS suppressor, resettable fuse, protection diodes, reverse-polarity protection, over-voltage protection, and 15kV ESD protection on the RS422 interface. An onboard 120Ω RS422 termination resistor can be enabled or disabled using an internal jumper. Screw-terminal connections and a compact ABS enclosure compatible with 35 mm DIN rails simplify installation in control cabinets and industrial automation systems.
Key Features
- Converts TTL signals to differential RS422 signals
- Supports full-duplex RS422 communication
- Compatible with 3.3V to 5V TTL signal levels
- Integrated galvanic power-supply isolation
- Integrated digital signal isolation
- Isolated side requires no separate external power supply
- Reverse-polarity protection on the power input
- Over-voltage protection on the power input
- TVS transient-voltage suppression
- 15kV ESD protection on the RS422 interface
- Resettable fuse for over-current protection
- Protection diodes for improved voltage and current protection
- Built-in 120Ω RS422 termination resistor
- Termination resistor enabled or disabled through an internal jumper
- Screw-terminal connections on TTL and RS422 sides
- TTL transmission distance of approximately 10 m
- RS422 transmission distance of approximately 1.2 km
- Supports point-to-point and point-to-multipoint communication
- Supports up to 256 RS422 nodes under specified network conditions
- ABS enclosure suitable for 35 mm DIN-rail installation
- Suitable for industrial automation and long-distance serial communication
Primary Function
Converting the TTL signal into a balanced differential RS422 signal
for interface conversion, expanding nodes, and long-distance communication
Rail-Mount Support
Easy To Combine Multi Rail-Mounted Serial Server, More Freely
Interface
* Note: the TTL TO RS422 (B) is designed to be used with RS422 devices; however, it can also possible to be used with RS485 devices (yet only sending is available). We recommend using TTL to RS485 (B) for an RS485 device.
Communication Connection Diagram
TTL converter to RS422, point-to-point, full-duplex communication, suitable for interface conversion
TTL converter to RS422, point-to-multipoint, full-duplex communication, suitable for expanding nodes
Two groups of TTL-to-RS422 conversion, point-to-point, full-duplex communication, suitable for extending the communication distance of TTL
Application Examples
The TTL TO RS422 (B) can be widely used for point-to-point, point-to-multipoint, long-distance cascaded communication networks between two hosts, or between a host and MCU/Peripheral. It can also be used in application scenarios that require TTL-to-RS422 conversion, such as Industrial Automation and IoT.
Dimensions
Package Includes:
- TTL TO RS422 (B) x1
- Screwdriver x1
