ADM485 Analog Devices, ADM485 Datasheet

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... Both the driver and the receiver may be enabled independently. When disabled, the outputs are three-stated. The ADM485 operates from a single 5 V power supply. Excessive power dissipation caused by bus contention or by output shorting is prevented by a thermal shutdown circuit. This feature forces ...

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... ADM485–SPECIFICATIONS Parameter DRIVER Differential Output Voltage OD3 ∆|V | for Complementary Output States OD Common-Mode Output Voltage ∆|V | for Complementary Output States OD Output Short-Circuit Current (V OUT Output Short-Circuit Current (V OUT CMOS Input Logic Threshold Low, V CMOS Input Logic Threshold High, V ...

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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the ADM485 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...

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... Ground Connection Noninverting Receiver Input A/Driver Output Inverting Receiver Input B/Driver Output B. Power Supply ± 5 PIN CONFIGURATION ADM485 TOP VIEW (Not to Scale GND 4 5 PIN FUNCTION DESCRIPTIONS –4– ...

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... PHL A, B 90% POINT RO 10% POINT 1. 0. – 0. –5– ADM485 OUT DE IN Test Circuit 4. Driver Enable/Disable A V OUT Test Circuit 5. Receiver Propagation Delay +1. –1. ...

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... ADM485–Typical Performance Characteristics 0.25 0.50 0.75 1.00 1.25 OUTPUT VOLTAGE – V TPC 1. Output Current vs. Receiver Output Low Voltage 0 –2 –4 –6 –8 –10 –12 –14 –16 –18 3.50 3.75 4.00 4.25 OUTPUT VOLTAGE – V TPC 2. Output Current vs. Receiver Output High Voltage 4.55 4.50 4.45 4.40 4.35 4.30 4.25 4.20 4.15 –50 –25 ...

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... TEMPERATURE – C TPC 9. Supply Current vs. Temperature REV. E 0.7 0.6 0.5 0.4 0.3 0.2 0.1 3.0 3.5 4.0 4.5 –50 3.5 4.0 4.5 5.0 1.4 1.2 1.0 0.8 0.6 0.4 0.2 75 100 125 –7– ADM485 | t – t PLH PHL 0 –50 – TEMPERATURE – C TPC 10. Rx Skew vs. Temperature – PHLA PHLB – PLHA PLHB 0 – TEMPERATURE – ...

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... ADM485 1, 2 TPC 13. Unloaded Driver Differential Outputs 1, 2 TPC 14. Loaded Driver Differential Outputs TPC 15. Driver/Receiver Propagation Delays Low to High TPC 16. Driver/Receiver Propagation Delays High to Low TPC 17. Driver Output at 30 Mbps –8– ...

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... Figure 5. Typical RS-485 Network Thermal Shutdown The ADM485 contains thermal shutdown circuitry that protects the part from excessive power dissipation during fault conditions. RS-485 Shorting the driver outputs to a low impedance source can result Differential in high driver currents. The thermal sensing circuitry detects the 4000 ft ...

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... ADM485 0.25 (0.0098) 0.10 (0.0040) COPLANARITY OUTLINE DIMENSIONS 8-Lead Standard Small Outline Package [SOIC] (R-8) Dimensions shown in millimeters and (inches) 5.00 (0.1968) 4.80 (0.1890 6.20 (0.2440) 4.00 (0.1574) 5.80 (0.2284) 3.80 (0.1497 1.27 (0.0500) 1.75 (0.0688) BSC 1.35 (0.0532) 0.51 (0.0201) 0.25 (0.0098) 0.31 (0.0122) SEATING 0.10 0.17 (0.0067) PLANE COMPLIANT TO JEDEC STANDARDS MS-012AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS ...

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... PLANE 0.060 (1.52) 0.022 (0.56) 0.050 (1.27) 0.018 (0.46) 0.045 (1.14) 0.014 (0.36) COMPLIANT TO JEDEC STANDARDS MO-095AA CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN –11– ADM485 0.150 (3.81) 0.135 (3.43) 0.120 (3.05) 0.015 (0.38) 0.010 (0.25) 0.008 (0.20) ...

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... ADM485 Revision History Location 10/03—Data Sheet changed from REV REV. E. Changes to TIMING SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Updated ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 7/03—Data Sheet changed from REV REV. D. Changes to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Changes to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Update to OUTLINE DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1/03—Data Sheet changed from REV REV. C. ...