Login - Register -

Parts - MAX485 Serial line transceivers


  • MAX485 module - RS485 to TTL RS232 transceiver board
  • Half-duplex operation (single twisted pair)
  • Max data rate: 2.5MBps
  • Max devices per bus: 32
  • Quiescent current: 300µA

Pinout description

  • A, B - the twisted pair comms line
  • Vcc, Gnd - Power 4.75V ≤ Vcc ≤ 5.25V
  • RO - Receiver output - ttl level serial RX
  • R̅E̅ - Receiver Output Enable - enabled when low
  • DI - Driver Input - ttl level serial TX
  • DE - Driver Output Enable - enabled when high

RS-485 uses a single twisted pair of wires to connect upto 32 devices together in a bus fashion, each end should be "terminated" with a 120ohm resistor across the pair. The system is half-duplex, so only one unit should be in transmit mode at a time, all others should be in receive mode, or off. RS-485 defines only the physical interface, it is up to the end user application to supply any protocol that is required.


- Last change August 17, 2018, at 12:34 PM
- Registered in England and Wales 08777436