Overview
The ADM485JR-REEL 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 EIA standards RS-485 and RS-422, making it suitable for various high-speed data transmission applications. The device operates from a single 5 V power supply and features thermal shutdown protection and short-circuit protection to ensure reliable operation.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | 4.75 | 5 | 5.25 | V | |
| Driver Propagation Delay (tDPLH) | 10 | 40 | 60 | ns | RDIFF = 54 Ω, CL1 = CL2 = 100 pF |
| Receiver Propagation Delay | 15 | ns | |||
| Output Skew (tSKEW) | 5 | 10 | ns | RDIFF = 54 Ω, CL1 = CL2 = 100 pF | |
| Rise/Fall Time (tDR, tDF) | 3 | 20 | 40 | ns | RDIFF = 54 Ω, CL1 = CL2 = 100 pF |
| Common-Mode Voltage Range | -7 | 12 | V | ||
| Driver Short-Circuit Current (IOSD1, IOSD2) | 35 | 250 | mA | -7 V ≤ VO ≤ +12 V | |
| Receiver Short-Circuit Current (IOSR) | 7 | 95 | mA | 0 V ≤ VO ≤ VCC | |
| ESD Protection | ±15 kV | Human body model | |||
| Package Type | SOIC-8 |
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
- Supports up to 32 transceivers on a bus, with only one driver enabled at a time
Applications
- Low power RS-485 systems
- DTE/DCE interfaces
- Packet switching and local area networks (LANs)
- Data concentration and data multiplexers
- Integrated services digital network (ISDN)
- Communication networks (optical fiber, wireless, satellite)
- Automotive electronics (vehicle entertainment, navigation, intelligent driving assistance)
- Industrial Internet of Things (IoT) applications (smart home, smart agriculture, smart logistics)
- Consumer electronics (smartphones, tablets, wearable devices)
Q & A
- What are the main standards that the ADM485JR-REEL complies with?
The ADM485JR-REEL complies with EIA RS-485 and RS-422 standards.
- What is the operating voltage range of the ADM485JR-REEL?
The operating voltage range is 4.75 V to 5.25 V.
- What is the typical driver propagation delay of the ADM485JR-REEL?
The typical driver propagation delay is 40 ns.
- What is the common-mode voltage range of the ADM485JR-REEL?
The common-mode voltage range is -7 V to +12 V.
- Does the ADM485JR-REEL have thermal shutdown protection?
Yes, it has thermal shutdown protection to prevent excessive power dissipation during fault conditions.
- How many transceivers can be connected on a bus simultaneously?
Up to 32 transceivers can be connected on a bus, but only one driver should be enabled at any time.
- What type of package does the ADM485JR-REEL use?
The ADM485JR-REEL uses an SOIC-8 package.
- Does the ADM485JR-REEL have ESD protection?
Yes, it has ESD protection of ±15 kV according to the human body model.
- What are some common applications of the ADM485JR-REEL?
Common applications include low power RS-485 systems, DTE/DCE interfaces, packet switching, local area networks, and various industrial and consumer electronics.
- What is the fail-safe state of the receiver output if the inputs are unconnected?
The receiver output will be in a logic high state if the inputs are unconnected.
