Overview
The ADM3485EAR-REEL is a 3.3 V, low-power, half-duplex transceiver designed for RS-485 and RS-422 communication protocols. Produced by Analog Devices Inc., this component is suitable for multipoint bus transmission lines and offers several key features that make it ideal for various industrial and commercial applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | 3.0 | 3.3 | 3.6 | V | |
| Data Rate | 12 | Mbps | |||
| Differential Output Delay (tDD) | 1 | 22 | 35 | ns | RL = 60 Ω, CL1 = CL2 = 15 pF |
| Differential Output Transition Time (tTD) | 3 | 11 | 25 | ns | RL = 60 Ω, CL1 = CL2 = 15 pF |
| Propagation Delay From Low to High Level (tPLH) | 7 | 23 | 35 | ns | |
| ESD Protection (A, B Pins) | ±15 kV | Human body model | |||
| Operating Temperature Range | -40 | 85 | °C | ||
| Storage Temperature Range | -65 | 150 | °C |
Key Features
- TIA/EIA RS-485/RS-422 compliant
- ±15 kV ESD protection on RS-485 input/output pins
- Low power consumption with a shutdown mode
- Half-duplex transceiver with separate enable inputs for the driver and the receiver
- Up to 32 nodes on the bus
- Receiver open-circuit, fail-safe design
- Thermal shutdown circuit to prevent excessive power dissipation
- Current limit protection on the output stage
- High impedance state for driver and receiver outputs when disabled
Applications
- Multipoint bus transmission lines
- Industrial I/O and automation systems
- Automotive interfaces (CAN, Audio, Ethernet)
- Home bus transceivers (HomeBus TxRx)
- IO-Link and other industrial communication protocols
- Point-to-point and daisy-chain network topologies
Q & A
- What is the maximum data rate of the ADM3485EAR-REEL?
The maximum data rate is up to 12 Mbps.
- What is the ESD protection level for the RS-485 input/output pins?
The ESD protection level is ±15 kV according to the human body model.
- What is the operating temperature range of the ADM3485EAR-REEL?
The operating temperature range is -40°C to +85°C.
- How many nodes can be connected on the bus using the ADM3485EAR-REEL?
Up to 32 nodes can be connected on the bus.
- What is the purpose of the thermal shutdown circuit in the ADM3485EAR-REEL?
The thermal shutdown circuit prevents excessive power dissipation caused by bus contention or output shorting by forcing the driver output into a high impedance state if the die temperature rises excessively.
- How does the receiver fail-safe feature work in the ADM3485EAR-REEL?
If the inputs are unconnected (floating), the receiver contains a fail-safe feature that results in a logic high output state.
- What is the package type and lead count of the ADM3485EAR-REEL?
The package type is 8-lead SOIC_N.
- Is the ADM3485EAR-REEL RoHS compliant?
Yes, the ADM3485EAR-REEL is lead-free and RoHS compliant.
- What are the typical applications of the ADM3485EAR-REEL?
Typical applications include multipoint bus transmission lines, industrial I/O, automotive interfaces, and home bus transceivers.
- How do you enable and disable the driver and receiver outputs in the ADM3485EAR-REEL?
The driver output is enabled with a high level on the DE pin and disabled with a low level. The receiver output is enabled with a low level on the RE pin and disabled with a high level.
