Features and Benefits
- UL Rated Isolated RS485: 2500VRMS
- UL Recognized File #E151738
- Eliminates Ground Loops
- 250kBd Maximum Data Rate
- Self-Powered with 420kHz Converter
- Half- or Full-Duplex
- Fail-Safe Output High for Open or Shorted Receiver Inputs
- Short-Circuit Current Limit
- Slow Slew Rate Control
- 68kΩ Input Impedance Allows Up to 128 Nodes
- Thermal Shutdown
- 8kV ESD Protection On Driver Outputs and Receiver Inputs
- Available in 28-Lead SW Package
The LTC1535 is an isolated RS485 full-duplex differential line transceiver. Isolated RS485 is ideal for systems where the ground loop is broken to allow for much larger common mode voltage ranges. An internal capacitive isolation barrier provides 2500VRMS of isolation between the line transceiver and the logic level interface. The powered side contains a 420kHz push-pull converter to power the isolated RS485 transceiver. Internal full-duplex communication occurs through the capacitive isolation barrier. The transceiver meets RS485 and RS422 requirements.
The driver and receiver feature three-state outputs, with the driver maintaining high impedance over the entire common mode range. The drivers have short-circuit current limits in both directions and a slow slew rate select to minimize EMI or reflections. The 68kΩ receiver input allows up to 128 node connections. A fail-safe feature defaults to a high output state when the receiver inputs are open or shorted.
- Isolated RS485 Receiver/Driver
- RS485 with Large Common Mode Voltage
- Breaking RS485 Ground Loops
- Multiple Unterminated Line Taps
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 241B showcases the LTC1535 isolated RS485 transceiver. The LTC1535 features 2,500V isolation; the “left-half” of the chip contains familiar RS485 logic functions and an isolated switching converter, and the “right-half” contains the RS485 transceiver. Both sides include a communications section to send data back and forth across the internal capacitive isolation barrier.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.