ADM2485BRWZ Analog Devices Inc, ADM2485BRWZ Datasheet
ADM2485BRWZ
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ADM2485BRWZ Summary of contents
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FEATURES Half-duplex, isolated RS-485 transceiver Integrated oscillator driver for external transformer PROFIBUS® compliant Complies with ANSI/TIA/EIA RS-485-A-98 and ISO 8482:1987(E) Data rate: 16 Mbps 3.3 V operation (V ) DD1 50 nodes on bus High common-mode transient ...
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ADM2485 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications .................................................................. 5 Package Characteristics ............................................................... 6 Regulatory Information............................................................... 6 Insulation and Safety-Related Specifications............................ 6 ...
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SPECIFICATIONS 2.7 V ≤ V ≤ 5.5 V, 4.75 V ≤ V ≤ 5. DD1 DD2 Table 1. Parameter DRIVER Differential Outputs Differential Output Voltage Δ|V | for Complementary Output States OD Common-Mode Output Voltage, V ...
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ADM2485 Parameter POWER SUPPLY CURRENT Logic Side Bus Side COMMON-MODE TRANSIENT IMMUNITY HIGH FREQUENCY COMMON-MODE NOISE IMMUNITY the maximum common-mode voltage slew rate that can be sustained while maintaining specification-compliant operation. V difference between the logic and ...
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TIMING SPECIFICATIONS 2.7 V ≤ V ≤ 5.5 V, 4.75 V ≤ V ≤ 5. DD1 DD2 Table 2. Parameter DRIVER Maximum Data Rate Propagation Delay Input-to-Output PLH PHL RTS-to-DE OUT Propagation Delay Driver Output-to-Output, ...
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ADM2485 PACKAGE CHARACTERISTICS Table 3. Parameter Resistance (Input-to-Output Capacitance (Input-to-Output) 2 Input Capacitance Input IC Junction-to-Case Thermal Resistance Output IC Junction-to-Case Thermal Resistance 1 Device considered a 2-terminal device: Pin 1 to Pin 8 are shorted together and ...
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VDE 0884-2 INSULATION CHARACTERISTICS This isolator is suitable for basic electrical isolation only within the safety limit data. Maintenance of the safety data must be ensured by means of protective circuits. An asterisk (*) on packages denotes DIN V VDE ...
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ADM2485 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. All voltages are relative to A their respective grounds. Table 7. Parameter V DD1 V DD2 Digital Input Voltage (RTS, RE, TxD) Digital Output Voltage RxD DE OUT D1, D2 ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 8. Pin Function Description Pin No. Mnemonic Function 1 D1 Transformer Driver Terminal Transformer Driver Terminal 2. 3 GND Ground, Logic Side Power Supply, Logic Side (3.3 V ...
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ADM2485 TYPICAL PERFORMANCE CHARACTERISTICS 2.40 2.35 I _RE_ENABLE_V DD1 DD1 2.30 2.25 2.20 2.15 2.10 I _DE_ENABLE_V = 5.5V DD2 DD1 2.05 2.00 –40 – TEMPERATURE (°C) Figure 7. Unloaded Supply Current vs. Temperature 5.0 I _PROFIBUS LOAD_TxD ...
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CH1 1.0V Ω CH2 1.0V Ω M10.0ns T 19.8000ns CH3 2.0V Ω Figure 13. Driver/Receiver Propagation Delay, High to Low ( Ω 100 pF) LDIFF L1 L2 350 300 250 SIDE 2 ...
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ADM2485 CH1 2.0V Ω CH2 2.0V Ω M400ns 125MS/s 8.0ns/pt Figure 19. Switching Waveforms (50 Ω Pull- and D2) DD1 1 A CH2 1.52V CH1 (Break-Before-Make, 50 Ω Pull- Rev. ...
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TEST CIRCUITS V OD Figure 21. Driver Voltage Measurement 375Ω V 60Ω OD3 375Ω Figure 22. Driver Voltage Measurement RTS TxD RxD RE V GND V DD1 1 DD2 Figure 23. Supply-Current Measurement Test Circuit RTS DE OUT TxD A ...
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ADM2485 CIRCUIT DESCRIPTION ELECTRICAL ISOLATION In the ADM2485, electrical isolation is implemented on the logic side of the interface. Therefore, the part has two main sections: a digital isolation section and a transceiver section (see Figure 30). Driver input and ...
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MAGNETIC FIELD IMMUNITY Because iCouplers use a coreless technology, no magnetic components are present and the problem of magnetic saturation of the core material does not exist. Therefore, iCouplers have essentially infinite dc field immunity. The following analysis defines the ...
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ADM2485 APPLICATIONS INFORMATION PCB LAYOUT The ADM2485 isolated RS-485 transceiver requires no external interface circuitry for the logic interfaces. Power supply bypassing is required at the input and output supply pins (see Figure 33). Bypass capacitors are most conveniently connected ...
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... CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. ORDERING GUIDE Model Data Rate (Mbps) 1 ADM2485BRWZ 16 1 ADM2485BRWZ-REEL7 RoHS Compliant Part. 10.50 (0.4134) 10.10 (0.3976 7.60 (0.2992) 7.40 (0.2913 ...
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ADM2485 NOTES Rev Page ...
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NOTES Rev Page ADM2485 ...
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ADM2485 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06021-0-12/07(A) Rev Page ...