EVALUATION KIT AVAILABLE MAX14853/MAX14855 2.75kV Isolated 500kbps/25Mbps Full-Duplex RMS RS-485/RS-422 Transceivers with 35kV ESD Protection and Integrated Transformer Driver General Description Benefits and Features The MAX14853/MAX14855 isolated RS-485/ Higher Integration Simplifies Designs RS-422 transceivers provide 2750V (60s) of galvanic Integrated LDO for Powering Cable Side RMS isolation between the cable-side (RS-485/RS-422 driver/ Integrated Transformer Driver for Power Transfer to receiver-side) and the UART-side of the device. Isolation Cable Side improves communication by breaking ground loops and High-Performance Transceiver Enables Flexible reduces noise when there are large differences in ground Designs potential between ports. These devices allow for robust Compliant with RS-485 EIA/TIA-485 Standard communication up to 500kbps (MAX14853) or 25Mbps 500kbps (MAX14853)/25Mbps (MAX14855) (MAX14855). Maximum Data Rate The MAX14853/MAX14855 include an integrated 450kHz Up to 128 Devices on the Bus transformer driver for power transfer to the cable-side of Slew-Rate Limited Outputs (MAX14853) the transceiver using an external transformer. An integrated Integrated Receiver Deglitch Filter Increases Noise LDO provides a simple and space-efficient architecture Immunity (MAX14853) for providing power to the cable-side of the IC. Integrated Protection Ensures for Robust Communication The MAX14853/MAX14855 include one drive channel 35kV ESD (HBM) on Driver Outputs/Receiver and one receive channel. The receiver is -unit load, Inputs allowing up to 128 transceivers on a common bus. 2.75kV Withstand Isolation Voltage for 60s (V ) RMS ISO Integrated true fail-safe circuitry ensures a logic-high on 630V Maximum Repetitive Peak Isolation PEAK the receiver output when inputs are shorted or open. Voltage (V ) IORM Undervoltage lockout disables the driver when cable-side 445V Maximum Working Isolation Voltage RMS or UART-side power supplies are below functional levels. (V ) IOWM The driver outputs and receiver inputs are protected > 30 Years Lifetime at Rated Working Voltage from 35kV electrostatic discharge (ESD) to GNDB on Withstands 10kV Surge per IEC 61000-4-5 the cable-side, as specified by the Human Body Model Thermal Shutdown (HBM). The MAX14853/MAX14855 are available in a wide body 16-pin SOIC package and operate over the -40C to +105C temperature range. Functional Diagram Applications V TD1 TD2 V DDA LDO Industrial Automation Equipment MAX14853 Programmable Logic Controllers MAX14855 LDO HVAC XFMR DRIVER V DDB Power Meters RE A Safety Regulatory Approvals RXD B UL According to UL1577 TXD Z cUL According to CSA Bulletin 5A DE Y GNDA GNDB Ordering Information appears at end of data sheet. 19-7546 Rev 5 10/17 RS-485 TRANSCEIVERMAX14853/MAX14855 2.75kV Isolated 500kbps/25Mbps Full-Duplex RMS RS-485/RS-422 Transceivers with 35kV ESD Protection and Integrated Transformer Driver Absolute Maximum Ratings V to GNDA .......................................................-0.3V to +6V DDA V to GNDB .......................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) DDB A V to GNDB .....................................................-0.3V to +16V 16-pin Wide SOIC LDO TD1, TD2 to GNDA ..............................................-0.3V to +12V (derate 14.1mW/C above +70C) .........................1126.8mW TXD, DE, RE to GNDA ...........................................-0.3V to +6V Operating Temperature Range ......................... -40C to +105C RXD to GNDA.........................................-0.3V to (V + 0.3V) Junction Temperature ......................................................+150C DDA A, B, Y, Z to GNDB ...................................................-8V to +13V Storage Temperature Range ............................ -65C to +150C TD1, TD2 Continuous Current .............................................1.4A Lead Temperature (soldering, 10s) .................................+300C Short-Circuit Duration (RXD to GNDA, A, B, Y, Z, Soldering Temperature (reflow) .......................................+260C V to GNDB) ...................................................Continuous DDB Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Package Thermal Characteristics (Note 1) Junction-to-Ambient Thermal Resistance ( ) ..............71C/W Junction-to-Case Thermal Resistance ( ) ...................23C/W JA JC Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. DC Electrical Characteristics (V - V = 3.0V to 5.5V, V - V = 3.0V to 5.5V, T = T to T , unless otherwise noted. Typical values are at DDA GNDA DDB GNDB A MIN MAX V - V = 3.3V, V - V = 3.3V, V = V , and T = +25C.) (Notes 2, 3) DDA GNDA DDB GNDB GNDA GNDB A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER V 3.0 5.5 DDA Supply Voltage V V 3.0 5.5 DDB V = 5V, DE = high, RE = TXD = DDA I low, RXD unconnected, no load, 4.7 7.7 DDA TD1/TD2 unconnected Supply Current mA DE = high, RE = TXD = low, RXD I 7.4 12.5 DDB unconnected, no load, V = 3.3V DDB RE, RXD, DE, TXD 1.50 1.58 1.65 V Undervoltage Lockout UVLOA TD1/TD2 driver 2.55 2.7 2.85 V Threshold V 2.55 2.7 2.85 UVLOB RE, RXD, DE, TXD 50 V Undervoltage Lockout UVHYSTA TD1/TD2 driver 200 mV Threshold Hysteresis V 200 UVHYSTB TRANSFORMER DRIVER Output Resistance R TD1/TD2 = low, I = 300mA 0.6 1.5 O OUT 4.5V V 5.5V 540 785 1300 DDA TD1, TD2 Current Limit I mA LIM 3.0V V 3.6V 485 730 1170 DDA Switching Frequency f 350 450 550 kHz SW Duty Cycle D 50 % Crossover Dead Time t 50 ns DEAD Maxim Integrated 2 www.maximintegrated.com