Overview
The ADM1485AR from Analog Devices Inc. is a high-speed, low-power differential line transceiver designed for bidirectional data communication on multipoint bus transmission lines. It complies with both EIA Standards RS-485 and RS-422, making it suitable for a wide range of applications requiring balanced data transmission. The device operates from a single 5 V power supply and features a thermal shutdown circuit to prevent excessive power dissipation during fault conditions. The ADM1485AR is fabricated using BiCMOS technology, combining the benefits of low power CMOS with the fast switching speeds of bipolar technology.
Key Specifications
| Parameter | Value | Unit | Comments |
|---|---|---|---|
| Manufacturer | Analog Devices, Inc. | ||
| Voltage - Supply | 4.75V ~ 5.25V | V | |
| Type | Transceiver | ||
| Supplier Device Package | 8-SOIC | ||
| Protocol | RS485 | Also compatible with RS422 | |
| Number of Drivers/Receivers | 1/1 | ||
| Mounting Type | Surface Mount | ||
| Operating Temperature | -40°C to 85°C | °C | |
| Driver Propagation Delay | 10 ns | ns | |
| Receiver Propagation Delay | 15 ns | ns | |
| Data Rate | Up to 30 Mbps | Mbps | |
| Common-Mode Voltage Range | -7 V to +12 V | V | |
| Thermal Shutdown | Yes | Activates at 150°C, re-enables at 140°C |
Key Features
- Compliance with EIA Standards RS-485 and RS-422
- High-speed data transmission up to 30 Mbps
- Low power consumption
- Single 5 V power supply
- Thermal shutdown protection to prevent excessive power dissipation
- Short-circuit protection
- High-Z outputs when powered down or disabled
- Fail-safe receiver input feature ensuring a logic high output state if inputs are unconnected
- BiCMOS technology for fast switching speeds and low power consumption
- ESD protection on all inputs and outputs
Applications
- Low power RS-485 systems
- DTE-DCE interfaces
- Packet switching networks
- Local Area Networks (LANs)
- Data concentration and multiplexers
- Integrated Services Digital Network (ISDN)
Q & A
- What is the operating voltage range of the ADM1485AR?
The ADM1485AR operates from a single 5 V power supply, with a voltage range of 4.75V to 5.25V.
- What protocols does the ADM1485AR support?
The ADM1485AR supports both EIA Standards RS-485 and RS-422.
- What is the maximum data rate supported by the ADM1485AR?
The ADM1485AR can transmit data at rates up to 30 Mbps.
- What type of protection does the ADM1485AR have against excessive power dissipation?
The ADM1485AR features thermal shutdown protection that disables the driver outputs if a significant temperature increase is detected.
- What is the common-mode voltage range of the ADM1485AR?
The common-mode voltage range is from -7 V to +12 V.
- How many drivers and receivers are included in the ADM1485AR?
The ADM1485AR includes one driver and one receiver.
- What is the propagation delay for the driver and receiver of the ADM1485AR?
The driver propagation delay is 10 ns, and the receiver propagation delay is 15 ns.
- Does the ADM1485AR have ESD protection?
Yes, the ADM1485AR has ESD protection on all inputs and outputs.
- What is the fail-safe feature of the receiver input in the ADM1485AR?
The receiver input includes a fail-safe feature that ensures a logic high output state if the inputs are unconnected or floating.
- What is the operating temperature range of the ADM1485AR?
The operating temperature range is from -40°C to 85°C.
