Overview
The ADM485ARM, produced by Analog Devices Inc., is a 5 V low power EIA RS-485 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 differential line driver and a differential line receiver, both of which can be enabled independently. The ADM485ARM is fabricated using BiCMOS technology, combining low power CMOS with fast switching bipolar technology, ensuring high speed and low power consumption.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | 4.5 | 5 | 5.5 | V | |
| Data Rate | 5 | Mbps | |||
| Driver Propagation Delay (tPLH, tPHL) | 10 | ns | |||
| Receiver Propagation Delay (tPLH, tPHL) | 15 | ns | |||
| Bus Common-Mode Range | -7 | +12 | V | ||
| Operating Temperature Range | -40 | +85 | °C | ||
| Package Type | 8-Lead MSOP |
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 powered off or disabled
- True fail-safe receiver inputs ensuring a logic high output when inputs are open or shorted
- ESD protection on RS-485 I/O pins
- Slew rate limited driver outputs to reduce EMI
Applications
- Low power RS-485 systems
- DTE/DCE interfaces
- Packet switching
- Local area networks (LANs)
- Data concentration and data multiplexers
- Integrated services digital network (ISDN)
- EMI sensitive systems
- Industrial control systems
Q & A
- What is the primary function of the ADM485ARM?
The ADM485ARM is a differential line transceiver designed for high-speed bidirectional data communication on multipoint bus transmission lines, complying with EIA RS-485 and RS-422 standards.
- What is the operating voltage of the ADM485ARM?
The ADM485ARM operates from a single 5 V power supply.
- What is the maximum data rate supported by the ADM485ARM?
The ADM485ARM supports a maximum data rate of 5 Mbps.
- What protection features does the ADM485ARM have?
The ADM485ARM features thermal shutdown protection, short-circuit protection, and ESD protection on RS-485 I/O pins.
- How many transceivers can be connected on a bus using the ADM485ARM?
Up to 32 transceivers can be connected simultaneously on a bus.
- What is the significance of the high-Z outputs in the ADM485ARM?
The high-Z outputs minimize the loading effect on the bus when the transceiver is not in use or powered down.
- What is the fail-safe feature in the receiver inputs of the ADM485ARM?
The receiver inputs have a true fail-safe feature, ensuring a logic high output state if the inputs are unconnected or shorted.
- What is the slew rate limitation in the ADM485ARM?
The driver outputs are slew rate limited to reduce EMI and data errors caused by reflections from improperly terminated buses.
- What are the common applications of the ADM485ARM?
The ADM485ARM is commonly used in low power RS-485 systems, DTE/DCE interfaces, packet switching, local area networks, data concentration, data multiplexers, and ISDN.
- What is the operating temperature range of the ADM485ARM?
The ADM485ARM operates over a temperature range of -40°C to +85°C.
