EVALUATION KIT AVAILABLE MAX14856/MAX14858 5kV Isolated 500kbps/25Mbps Full-Duplex RMS RS-485/RS-422 Transceivers with 35kV ESD Protection General Description Benefits and Features The MAX14856/MAX14858 isolated RS-485/RS-422 High-Performance Transceiver Enables Flexible Designs transceivers provide 5000V (60s) of galvanic Integrated LDO for Cable Side Power RMS isolation between the cable side (RS-485/RS-422 driver/ Compliant with RS-485 EIA/TIA-485 Standard 500kbps (MAX14856)/25Mbps (MAX14858) receiver-side) and the UART side of the device. Isolation improves communication by breaking ground loops and Maximum Data Rate Allows Up to 128 Devices on the Bus reduces noise when there are large differences in ground potential between ports. These devices allow for robust Integrated Protection Ensures for Robust communication up to 500kbps (MAX14856) or 25Mbps Communication (MAX14858). 35kV ESD (HBM) on Driver Outputs/Receiver Inputs The devices include one drive channel and one receive 5kV Withstand Isolation Voltage for 60 RMS Seconds (V ) channel. The receiver is 1/4-unit load, allowing up to 128 ISO 1200V Maximum Repetitive Peak-Isolation transceivers on a common bus. PEAK Voltage (V ) IORM Integrated true fail-safe circuitry ensures a logic-high on the 848V Maximum Working-Isolation Voltage RMS receiver output when inputs are shorted or open. Undervoltage (V ) IOWM lockout disables the driver when the cable side or UART side > 30 Years Lifetime at Rated Working Voltage power supplies are below functional levels. Withstands 10kV Surge per IEC 61000-4-5 The driver outputs and receiver inputs are protected Thermal Shutdown from 35kV electrostatic discharge (ESD) to GNDB on Safety Regulatory Approvals the cable side, as specified by the Human Body Model (HBM). UL According to UL1577 cUL According to CSA Bulletin 5A The devices are available in a wide-body 16-pin SOIC package and operate over the -40C to +105C Applications temperature range. Industrial Automation Equipment Programmable Logic Controllers HVAC Power Meters Functional Diagram VDDA VLDO MAX14856 MAX14858 LDO VDDB Ordering Information appears at end of data sheet. SBA RXD A RE B TXD Z Y DE GNDA GNDB 19-7966 Rev 1 1/17 RS-485 TRANSCEIVERMAX14856/MAX14858 5kV Isolated 500kbps/25Mbps Full-Duplex RMS RS-485/RS-422 Transceivers with 35kV ESD Protection Absolute Maximum Ratings V to GNDA ......................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) DDA A V to GNDB .......................................................-0.3V to +6V 16-pin Wide SOIC DDB V to GNDB .....................................................-0.3V to +16V (derate 14.1mW/C above +70C) ..........................1126.8mW LDO TXD, DE, RE to GNDA ...........................................-0.3V to +6V Operating Temperature Range ......................... -40C to +105C SBA, RXD to GNDA ............................. -0.3V to (V + 0.3V) Junction Temperature ......................................................+150C DDA A, B, Z, Y to GNDB ..................................................-8V to +13V Storage Temperature Range ............................ -65C to +150C Short Circuit Duration (RXD, SBA to GNDA, Lead Temperature (soldering, 10s) .................................+300C A, B, Y, Z ,V to GNDB) ...................................Continuous Soldering Temperature (reflow) .......................................+260C 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 = 1.71V to 5.5V, V V = 3.0V to 5.5V, T = T to T , unless otherwise noted. Typical values are DDA GNDA DDB GNDB A MIN MAX at 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 1.71 5.5 DDA Supply Voltage V V 3.0 5.5 DDB V = 5V, DE = high, RE = TXD = low, DDA I 3.9 6.6 DDA RXD unconnected, no load Supply Current mA DE = high, RE = TXD = low, RXD I 7 12.5 DDB unconnected, no bus load, V = 3.3V DDB V V rising 1.50 1.58 1.65 Undervoltage-Lockout UVLOA DDA V Threshold V V rising 2.55 2.7 2.85 UVLOB DDB V 50 Undervoltage-Lockout UVHYSTA mV Threshold Hysteresis V 200 UVHYSTB LDO LDO Supply Voltage V Relative to GNDB, LDO is on (Note 4) 3.18 14 V LDO DE = high, TXD = low, no bus load, LDO Supply Current I 7.5 12.9 mA LDO V = 5.5V LDO LDO Output Voltage V 3.0 3.3 3.6 V DDB LDO Current Limit 300 mA Load Regulation V = 3.3V, I = 20mA to 40mA 0.19 1.7 mV/mA LDO LOAD Line Regulation V = 3.3V to 14V, I = 20mA 0.12 1.8 mV/V LDO LOAD Dropout Voltage V = 3.18V, I = -120mA 100 180 mV LDO DDB Maxim Integrated 2 www.maximintegrated.com