RS-485
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Contents |
Information
RS-485 is a two-wire, half-duplex, multipoint serial communications channel, that can span relatively large distances (up to 1,200 m).
- Mode of Operation
- Differential
- Total number of receivers and drivers on one line
- 32 receivers, 32 drivers (one active at a time)
- Maximum cable length
- 1200 meters (4000 feet)
- Maximum data rate
- 10Mb/s to 100Kb/s (12 m. (40ft.) to 1200 m.)
- Maximum driver output voltage
- -7V to +12V
- Driver output signal level
- +/-1.5V (loaded) - +/-6V (unloaded)
- Driver load impedance
- 54 ohms
- Maximum driver current in high Z state
- +/-100uA
- Receiver input voltage range
- -7V to +12V
- Receiver input sensitivity
- +/-200mV
- Receiver input resistance
- >=12kohms (1 Standard Load)
RS-485 <-> RS-232
Resources
Files
- Datablad: DIFFERENTIAL BUS TRANSCEIVERS
- RS-422 and RS-485 Application Note
- Ten Ways to Bulletproof RS485
- Datablad: SN75176B transceiver
