This interface is similar to RS485 interface. The RS422 interface is used for multi drop configuration and supports up to 10 devices at a time. It is used in balanced differential mode. It supports data rate from 100 kbps to about 10 Mbps.
Figure depicts RS 422 pin configuration for 9 pin connector.
RS422 Technical Specifications
Following table-1 describes RS422 technical specifications.
|Mode of operation||Differential|
|number of drivers/receivers on one line||1 driver, 10 receiver|
|maximum cable length||4000 feet|
|maximum data rate||10 Mbps|
|max. driver output voltage||-0.25V to +6V|
|Max. driver current in high impedance state (power off)||+/-100 µA|
|receiver input voltage range||-10V to +10V|
|Receiver input sensitivity||+/-200mV|
|Driver load impedance||100 Ohms|
|Receiver Input Resistance||4K min.|