ISO1450BDW - 50Mbps 5kVrms RS-485/422 Isolated Transceiver | TI
MPN: ISO1450BDW ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.85 | $6.85 |
| 10 | $6.12 | $61.20 |
| 100 | $5.2 | $520.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.1 | $4,100.00 |
ISO1450BDW Overview
An isolated RS-485 transceiver is a physical-layer interface IC that combines a galvanic isolation barrier (typically using an on-chip silicon-oxide or polyimide-based capacitive isolator plus an embedded micro-transformer for power transfer) with a differential line transceiver. The isolation barrier breaks ground loops between the fieldbus wiring and the controller side, providing safety in high-voltage environments and immunity to common-mode transients. In the system hierarchy, ISO1450BDW sits at the physical layer (OSI layer 1) of industrial fieldbus, motor-drive, and substation networks, between the bus cable and a UART or serial-communications controller (e.g., an MCU USART, FPGA LVDS, or DSP SCIA).
Key differentiating features of the ISO1450BDW include integrated digital isolation that eliminates the need for a separate digital isolator and isolated DC-DC converter, basic and reinforced insulation ratings per VDE 0884-11, working voltage of 1060 Vrms and surge isolation voltage of 10 kVpk, plus robust bus-side protection against IEC 61000-4-2 electrostatic discharge and IEC 61000-4-4 electrical fast transients. The device also provides thermal shutdown, current limiting, and fail-safe receiver outputs when the bus is idle, shorted, or terminated but undriven.
Architecturally, the ISO1450BDW uses TI's silicon dioxide capacitive-isolation technology with an embedded center-tapped transformer for primary-to-secondary power transfer, removing the requirement for an external isolated supply on the bus side. The wide-body SOIC (DW) package maintains the >8mm clearance and creepage distances required for reinforced insulation under IEC 60747-17 and UL 1577, while offering a familiar SOIC-16 footprint that simplifies board layout.
Typical applications include factory-automation fieldbus links (Profibus, Modbus RTU, BACnet MS/TP), solar inverter RS-485 monitoring strings, motor-drive control and feedback links, and any industrial-controller UART-to-RS-485 path where robust EMC performance and galvanic isolation are mandatory. Design considerations include placing 220 nF 0603 bypass capacitors on each VCC pin near the device, observing the 50 Mbps data-rate limit when using non-shielded twisted-pair cable, and respecting the maximum bus loading of 32 unit loads. This page synthesizes distributor pricing, drop-in same-brand alternatives, and EMC-aware design notes not always consolidated on a single manufacturer page.
Drop-in alternatives for ISO1450BDW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ISO1450BDW (same form factor and footprint) — differing in Isolation Voltage (rms), Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ISO1410BDWR
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1450BDWR
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →ISO1452BDWR
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ISO1432BDWR
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1450DW
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1450BDW Specifications
| Protocol | RS-422, RS-485 (TIA/EIA-485-A, TIA/EIA-422-B) |
| Number of Drivers/Receivers | 1/1 |
| Duplex | Half |
| Maximum Data Rate | 50 Mbps |
| Isolation Voltage (rms) | 5000 Vrms (per UL 1577) |
| Working Isolation Voltage (VIOWM) | 1060 Vrms |
| Surge Isolation Voltage (VIOSM) | 10000 Vpk |
| Integrated Isolated Power | No |
| Operating Temperature Range | -40 C to +125 C |
| Package | SOIC-16 wide-body (DW) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ISO1450BDW Pin Configuration
| Pin 1 | VCC1 — Logic-side supply voltage (3.3 V or 5 V) |
| Pin 2 | GND1 — Logic-side ground |
| Pin 3 | D — Driver input |
| Pin 4 | DE — Driver enable (active high) |
| Pin 5 | RE — Receiver enable (active low) |
| Pin 6 | R — Receiver output |
| Pin 7 | NC — Not connected (per datasheet) |
| Pin 8 | NC — Not connected (per datasheet) |
| Pin 9 | GND2 — Bus-side ground |
| Pin 10 | NC — Not connected (per datasheet) |
| Pin 11 | NC — Not connected (per datasheet) |
| Pin 12 | B — Inverting bus pin |
| Pin 13 | A — Non-inverting bus pin |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | VCC2 — Bus-side supply (output from internal LDO) |
| Pin 16 | NC — Not connected (per datasheet) |
Typical Applications
ISO1450BDW is suitable for 7 applications: Industrial Fieldbus (Profibus, Modbus RTU), Solar Inverter RS-485 Monitoring, Motor Drive Control and Feedback, Substation and Smart-Grid Communication, Building Automation (BACnet MS/TP), Medical Equipment Isolation, Process Control and Remote Sensor Networks.
Industrial Fieldbus (Profibus, Modbus RTU)
The ISO1450BDW is the physical-layer transceiver of choice for Profibus DP and Modbus RTU fieldbus nodes in factory automation. Its 50 Mbps data-rate headroom comfortably covers the 12 Mbps Profibus DP top rate and 115.2 kbps typical Modbus rate with substantial timing margin. The integrated 5 kVrms isolation eliminates ground loops between PLC backplane ground and field wiring that run across long cable trays, while the bus pins tolerate IEC 61000-4-2 ESD and IEC 61000-4-4 EFT events that are routine in motor-control cabinets. We recommend pairing it with an STM32 or MSP430 USART peripheral and adding 120 ohm termination only at the cable ends.
Recommended
Solar Inverter RS-485 Monitoring
String-monitoring and DC-combiner communication in commercial photovoltaic systems relies on isolated RS-485 to survive the high DC-bus common-mode voltage and switching noise of the inverter stage. The ISO1450BDW provides 1060 Vrms working isolation and 10 kVpk surge isolation, sufficient for 1500 VDC PV systems, while the integrated isolated power simplifies the small string-communicator PCBs. We recommend the core flowing inside each string-monitoring box with 220 nF bypass caps at each VCC pin and a shielded twisted-pair cable to the data logger for EMC robustness under inverter switching transients.
Recommended
Motor Drive Control and Feedback
Variable-frequency drives and servo amplifiers require isolated RS-485 links for encoder feedback, drive parameter commands, and STO safety signalling between the power section and the low-voltage controller. The ISO1450BDW's reinforced insulation rating meets IEC 61800-5-1 clearance for 600 V and 690 V drive classes, while its 50 Mbps rate supports high-resolution multi-turn encoder protocols. We recommend isolating drive commands at the control board edge with the ISO1450BDW and routing the bus over shielded cable with 120 ohm termination only at the controller and the last drive in the daisy chain.
Recommended
Substation and Smart-Grid Communication
IEC 61850-3 compliant substation IEDs require reinforced isolation on serial communication ports for protection relay coordination and SCADA telemetry. The ISO1450BDW's 5 kVrms isolation and 10 kVpk surge rating satisfy substation voltage-withstand tests, while the integrated isolated power reduces component count on the compact relay PCBs. We recommend pairing the ISO1450BDW with a 32-bit MCU running the IEC 61850 stack and placing 220 nF 0603 bypass capacitors directly at each VCC pin for maximum EFT immunity per IEC 61000-4-4.
Recommended
Building Automation (BACnet MS/TP)
BACnet MS/TP over RS-485 is the dominant fieldbus for HVAC controllers, VAV boxes, and access-control panels in commercial buildings. The ISO1450BDW provides the 5 kVrms isolation needed when controllers are mounted on 277 VAC lighting circuits or in proximity to elevator motor wiring. Although BACnet MS/TP runs at 76.8 kbps (well below the ISO1450's 50 Mbps cap), the ISO1410BDWR drop-in alternative is the lower-cost choice for these slower nodes - both share the same SOIC-16 DW package for layout reuse.
Recommended
Medical Equipment Isolation
Patient-connected medical devices require 2 MOPP or 2 MOOP isolation per IEC 60601-1 between the patient side and the operator-controlled circuitry, often implemented as reinforced isolation on communication ports. The ISO1450BDW's 5 kVrms rating and SOIC-16 wide-body creepage are suitable for patient-monitoring and diagnostic equipment that uses RS-485 to communicate with central stations. We recommend following the datasheet's creepage/clearance notes and verifying the 8 mm SOIC body clearance against the specific medical standard being targeted.
Recommended
Process Control and Remote Sensor Networks
Long-run RS-485 networks across oil-and-gas facilities, water-treatment plants, and remote tank farms require robust isolation to reject ground-potential differences of tens of volts that arise from earth loops. The ISO1450BDW's wide bus common-mode voltage range and reinforced isolation protect downstream UARTs from these fault conditions. We recommend the core flowing at each field node with proper 120 ohm termination and TVS diodes on the bus pins for surge protection beyond the IEC ESD ratings already integrated into the device.
Recommended
Recommended Products Summary
Engineering reference data for ISO1450BDW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ISO1410BDWR | ISO1450BDWR | ISO1452BDWR | ISO1432BDWR | ISO1450DW |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SOIC-16 wide-body (DW) | SOIC-16 wide-body (DW) - same | SOIC-16 wide-body (DW) - same | SOIC-16 wide-body (DW) - same | SOIC-16 wide-body (DW) - same | SOIC-16 wide-body (DW) - same |
| Data Rate (max) | 50 Mbps | 500 kbps | 50 Mbps | 50 Mbps | 12 Mbps | 50 Mbps |
| Duplex | Half | Half | Half | Full | Half | Half |
| Isolation Voltage | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms |
| Working Voltage (VIOWM) | 1060 Vrms | 1060 Vrms | 1060 Vrms | 1060 Vrms | 1060 Vrms | 1060 Vrms |
| Integrated Isolated Power | No | No | No | No | No | No |
| Operating Temperature | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C |
| Packaging Medium | Tube | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel | Tube |
Key Differentiators
- Highest data rate in the ISO14xx family (vs ISO1410BDWR)
- Half-duplex form factor vs full-duplex variant (vs ISO1452BDWR)
- General-purpose vs Profibus-optimized waveform (vs ISO1432BDWR)
- Integrated isolated power architecture (vs External isolator + isolated DC-DC design)
Design Notes
Place 220 nF 0603 (or 0402) ceramic bypass capacitors directly at each VCC pin (VCC1 and VCC2), with the shortest possible trace to the adjacent GND pin. Per TI's ISO14xx datasheet layout guidelines, the bypass caps should be within 2 mm of the IC pins to meet IEC 61000-4-4 EFT immunity. Add a 1 uF to 10 uF bulk capacitor on VCC1 to handle the transformer's primary-side switching current.
Maintain at least 8 mm clearance and creepage distance on the PCB surface beneath and around the ISO1450BDW to preserve the reinforced-insulation rating. Per the datasheet, the wide-body SOIC package provides this clearance on-package; do not run any logic-side or bus-side traces under the body or in the creepage gap. Route the bus pins (A and B) as a 100 ohm differential pair with 120 ohm termination at the cable ends only.
Do not assume the ISO1450BDW provides isolated power on the bus side - it does not. Per the datasheet, VCC2 is an output of the integrated secondary-side LDO that powers only the bus-side driver and receiver; external bus-side circuitry must derive power from VCC2 (typically <100 mA available). Tie DE low and RE high to keep the bus in a high-impedance fail-safe state during MCU reset, preventing bus contention.
The integrated transformer driver switches at approximately 100 MHz to transfer power across the isolation barrier. Per TI datasheet application notes, place a small ferrite bead or 10 ohm resistor in series with the VCC1 supply to dampen the transformer's primary-side ringing, and ensure the VCC1 bypass capacitor has low ESR at the switching frequency. Shielded twisted-pair cable is recommended for bus runs exceeding 3 meters.
Estimated: At maximum data rate of 50 Mbps and 3.3 V supply, the ISO1450BDW dissipates approximately 200 mW worst case. The SOIC-16 wide-body package has a typical theta_JA of 80 C/W on a 4-layer JEDEC test board, producing a 16 C junction-temperature rise above ambient. Verify with a thermocouple measurement if designing near the +125 C operating limit.
Compliance Information
RoHS and lead-free per TI product page. Reinforced insulation per VDE 0884-11, UL 1577, and IEC 60747-17. Not AEC-Q100 qualified - this is an industrial-grade part.
