Overview
The ADM485ARZ-REEL, produced by Analog Devices Inc., is a differential line transceiver designed for high-speed bidirectional data communication on multipoint bus transmission lines. It complies with EIA standards RS-485 and RS-422, making it suitable for balanced data transmission. The device operates from a single 5 V power supply and features a BiCMOS technology that combines low power CMOS with fast switching bipolar technology. This transceiver is ideal for applications requiring high speed, low power, and robust communication over long distances.
Key Specifications
| Parameter | Rating/Value |
|---|---|
| Supply Voltage (VCC) | −0.3 V to +7 V |
| Driver Input (DI) | −0.3 V to VCC + 0.3 V |
| Control Inputs (DE, RE) | −0.3 V to VCC + 0.3 V |
| Receiver Inputs (A, B) | −9 V to +14 V |
| Driver Outputs (A, B) | −9 V to +14 V |
| Receiver Output | −0.5 V to VCC + 0.5 V |
| Data Rate | Up to 5 Mbps |
| Bus Common-Mode Range | −7 V to +12 V |
| Driver Propagation Delay | 10 ns typical |
| Receiver Propagation Delay | 15 ns typical |
| Thermal Shutdown Temperature | 150°C (disable), 140°C (re-enable) |
Key Features
- Meets EIA RS-485 and RS-422 standards
- Single 5 V power supply
- High speed, low power BiCMOS technology
- Thermal shutdown protection and short-circuit protection
- High-Z outputs when power is off or driver is disabled
- Fail-safe receiver output (logic high if inputs are unconnected)
- ESD protection on all inputs and outputs
- High source and sink current capability on driver outputs
- Minimal driver and receiver propagation delays
Applications
- Low power RS-485 systems
- DTE/DCE interface
- Packet switching
- Local area networks (LANs)
- Data concentration and data multiplexers
- Integrated services digital network (ISDN)
Q & A
- What are the primary standards that the ADM485 complies with?
The ADM485 complies with EIA standards RS-485 and RS-422.
- What is the operating voltage of the ADM485?
The ADM485 operates from a single 5 V power supply.
- What is the maximum data rate supported by the ADM485?
The ADM485 supports data rates up to 5 Mbps.
- What is the bus common-mode range of the ADM485?
The bus common-mode range is −7 V to +12 V.
- Does the ADM485 have thermal protection?
- How many transceivers can be connected on a bus simultaneously?
- What happens to the receiver output if the inputs are unconnected?
The receiver output defaults to a logic high state if the inputs are unconnected (floating).
- Does the ADM485 have ESD protection?
- What is the typical driver propagation delay of the ADM485?
- What is the typical receiver propagation delay of the ADM485?
