Overview
The ADM485JR-REEL7, 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 process, combining low power CMOS with fast switching bipolar technology. This transceiver is ideal for applications requiring high speed, low power, and robust protection against fault conditions.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions |
|---|---|---|---|---|---|
| Supply Voltage | 4.75 | 5 | 5.25 | V | |
| Data Rate | 5 | Mbps | |||
| Driver Propagation Delay (Low to High) | 10 | 40 | 60 | ns | RDIFF = 54 Ω, CL1 = CL2 = 100 pF |
| Receiver Propagation Delay | 15 | ns | |||
| Common-Mode Voltage Range | -7 | 12 | V | ||
| Driver Short-Circuit Current | 35 | 250 | mA | -7 V ≤ VO ≤ +12 V | |
| Receiver Short-Circuit Current | 7 | 95 | mA | 0 V ≤ VO ≤ VCC | |
| ESD Protection | ±15 kV | Human body model |
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 state (logic high if inputs are unconnected)
- ESD protection on all inputs and outputs
- High source and sink current capability on driver outputs
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)
Q & A
- What is the primary function of the ADM485JR-REEL7? The ADM485JR-REEL7 is a differential line transceiver for high-speed bidirectional data communication on multipoint bus transmission lines.
- What standards does the ADM485JR-REEL7 comply with? It complies with EIA standards RS-485 and RS-422.
- What is the operating voltage of the ADM485JR-REEL7? The device operates from a single 5 V power supply.
- What is the data rate capability of the ADM485JR-REEL7? It supports a data rate of up to 5 Mbps.
- What protection features does the ADM485JR-REEL7 have? It includes thermal shutdown protection, short-circuit protection, and ESD protection.
- How many transceivers can be connected on a bus? Up to 32 transceivers can be connected simultaneously on a bus, but only one driver should be enabled at any time.
- What is the common-mode voltage range of the ADM485JR-REEL7? The common-mode voltage range is from -7 V to +12 V.
- What is the fail-safe feature of the receiver output? The receiver output defaults to a logic high state if the inputs are unconnected (floating).
- What is the significance of the high-Z outputs when power is off or the driver is disabled? The high-Z outputs minimize the loading effect on the bus when the transceiver is not being used.
- What are some typical applications of the ADM485JR-REEL7? Typical applications include low power RS-485 systems, DTE/DCE interfaces, packet switching, local area networks, data concentration, data multiplexers, and ISDN.
