Part A
ADM485AR
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6742 PCS
- Package
- SOIC-8
- Series
- Interface - Condutores, Receptores, Transceivers
Replacement verdict
Compatible functional replacement candidate
The ADM483EAR-REEL is a functional replacement candidate for the ADM485AR, sharing the same RS-485 transceiver function, 8-pin SOIC package, and 5 V supply rail, while offering enhanced ESD protection and a higher driver output count. Designers should validate the increased ESD rating, the full-duplex-to-half-duplex configuration, and the exact data rate against the target application before substituting in production.
Function and Protocol
High match
Package Type
High match
ESD Protection Level
Validation required
Data Rate
Validation required
Parts at a glance
Part B
ADM483EAR-REEL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6191 PCS
- Package
- SOIC-8
- Series
- Interface - Condutores, Receptores, Transceivers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADM485AR | ADM483EAR-REEL | Why it matters |
|---|---|---|---|
| Data Rate | 5 Mbps | 250 kbps | Maximum signaling speed; a faster part can replace a slower one in most cases, but not vice versa if the bus runs above 250 kbps. |
| Duplex Mode | Half-duplex | Half-duplex | Determines whether the transceiver can transmit and receive simultaneously; both are half-duplex so bus topology compatibility is preserved. |
| Number of Drivers/Receivers | 1/1 | 1/1 | Confirms each device provides one differential driver and one receiver, matching the standard RS-485 point-to-multipoint node configuration. |
| Supply Voltage | 5 V | 5 V | Both operate from a single 5 V rail, so power supply design and logic-level interfacing remain unchanged when substituting. |
| ESD Protection (Bus Pins) | ±8 kV (contact, per datasheet HBM/ESD rating) | ±15 kV (IEC 61000-4-2, bus pins) | Higher ESD immunity improves robustness in harsh industrial environments; the enhanced part offers greater surge tolerance. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Both cover the industrial temperature range, so environmental operating limits are equivalent for substitution. |
| Package / Mounting | 8-SOIC (surface mount) | 8-SOIC (surface mount, tape and reel) | Identical footprint and package allow drop-in board replacement; the reel packaging affects assembly handling only. |
| Fail-Safe Receiver | Not specified / standard | True fail-safe (open/short/idle bus) | Fail-safe receivers guarantee a defined logic output when the bus is idle or floating, preventing spurious data in multi-node networks. |
| Driver Output / Receiver Input Compliance | RS-485 / RS-422 compatible | RS-485 / RS-422 compatible | Both meet the same differential signaling standards, ensuring interoperability on the same bus. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADM485AR | ADM483EAR-REEL |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Obsolete | Obsolete |
| Type | Transceiver | Transceiver |
| Protocol | RS422, RS485 | RS422, RS485 |
| Number of Drivers/Receivers | 1/1 | 1/1 |
| Duplex | Half | Half |
| Receiver Hysteresis | 70 mV | 70 mV |
| Data Rate | 5Mbps | 250kbps |
| Voltage - Supply | 4.75V ~ 5.25V | 4.5V ~ 5.5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary differences between the ADM485AR and ADM483EAR-REEL?
The ADM485AR is a 5 V, low-power RS-485 transceiver specified for data rates up to 5 Mbps, supplied in an 8-lead SOIC package. The ADM483EAR-REEL is a 5 V, ±15 kV ESD-protected RS-485/RS-422 transceiver with a reduced slew rate supporting data rates up to 250 kbps, supplied in an 8-lead SOIC and delivered on tape and reel. The ADM483EAR-REEL adds enhanced ESD protection and slew-rate-limited outputs for reduced EMI, while the ADM485AR offers higher data rate capability.
Are the ADM485AR and ADM483EAR-REEL pin-compatible?
Yes. Both devices are offered in the standard 8-lead SOIC (R-8) package with the same pinout: RO, RE, DE, DI, GND, A, B, and VCC. This allows the ADM483EAR-REEL to be used in place of the ADM485AR on the same PCB footprint, provided the lower data rate and slew-rate-limited output of the ADM483EAR-REEL are acceptable for the application.
What data rate does each device support?
The ADM485AR supports data rates up to 5 Mbps. The ADM483EAR-REEL is a slew-rate-limited device supporting data rates up to 250 kbps. The lower slew rate of the ADM483EAR-REEL reduces electromagnetic interference (EMI) and reflections on improperly terminated buses, but it cannot be used in applications requiring data rates above 250 kbps.
What is the ESD protection level of each device?
The ADM483EAR-REEL provides enhanced ESD protection of ±15 kV on the RS-485 bus pins (A and B) using the human body model (HBM), and is also specified for ±15 kV IEC 61000-4-2 air discharge and ±8 kV contact discharge. The ADM485AR provides standard ESD protection typical of the ADM485 family, which is lower than the enhanced ±15 kV level of the ADM483EAR-REEL. For bus-exposed applications requiring high ESD immunity, the ADM483EAR-REEL is the appropriate choice.
What are the supply voltage and quiescent current specifications?
Both devices operate from a single 5 V ±5% supply. The ADM485AR has a quiescent supply current typically around 300 µA to 500 µA in the enabled state, with a low-power shutdown current typically in the nanoampere range when the driver and receiver are disabled. The ADM483EAR-REEL has a similar low quiescent current profile, typically around 300 µA to 500 µA, making both suitable for power-sensitive RS-485 bus nodes.
Can the ADM483EAR-REEL directly replace the ADM485AR in an existing design?
In most cases yes, because both share the same 8-lead SOIC pinout and 5 V supply. However, the replacement is only valid if the system data rate does not exceed 250 kbps, since the ADM483EAR-REEL is slew-rate limited. The ADM483EAR-REEL also provides higher ESD protection, which is generally beneficial. The designer should verify that the reduced slew rate does not affect bus timing, cable length assumptions, or termination requirements in the target application.
What is the difference in packaging and ordering between the two parts?
The ADM485AR is supplied in an 8-lead SOIC package in tube or standard reel quantities depending on the ordering code. The ADM483EAR-REEL is specifically supplied on tape and reel (the "-REEL" suffix), which is suited to automated high-volume SMT assembly. Both use the same 8-lead SOIC body, so the PCB land pattern is identical; only the delivery format and quantity per reel differ.
Which device is better suited for noisy industrial environments?
The ADM483EAR-REEL is generally better suited for noisy industrial environments because of its ±15 kV ESD protection on the bus pins and its slew-rate-limited driver, which reduces EMI and high-frequency noise coupling. The ADM485AR is suitable for general-purpose RS-485 links up to 5 Mbps where enhanced ESD protection and reduced EMI are not critical requirements.