adm2485 Analog Devices, Inc., adm2485 Datasheet
adm2485
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adm2485 Summary of contents
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... DD1 RTS TxD RxD RE The ADM2485 driver has an active high enable. The driver differential outputs and the receiver differential inputs are connected internally to form a differential input/output port that imposes minimal loading on the bus when the driver is disabled or when V high receiver disable that causes the receive output to enter a high impedance state ...
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... Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications .................................................................. 4 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 ADM2485 Characteristics ............................................................... 6 Package Characteristics ............................................................... 6 Regulatory Information............................................................... 6 Insulation and Safety-Related Specifications............................ 6 VDE 0884-2 Insulation Characteristics..................................... 7 Pin Configuration and Function Descriptions............................. 8 REVISION HISTORY 1/07—Revision 0: Initial Version Test Circuits........................................................................................9 Switching Characteristics ...
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... Rev Page ADM2485 Unit Test Conditions/Comments ∞ (see Figure Ω (RS-422) (see Figure Ω (RS-485) (see Figure – ≥ 4.75 (see Figure 4) TST DD1 Ω Ω (see Figure Ω ...
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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 bus sides. The transient magnitude is the range over which the common mode is slewed. The common-mode voltage slew rates apply to both rising and falling common-mode voltage edges ...
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... 0.5 V DD1 ESD CAUTION –0 0.5 V DD1 –0 0.5 V DD2 13 V – +14 V –40°C to +85°C –55°C to +150°C – +35 mA 73°C/W 300°C 215°C 220°C Rev Page ADM2485 ...
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... JCI θ 28 JCO Notes In accordance with UL 1577, each ADM2485 is proof tested by applying an insulation test voltage ≥3000 V rms for 1 second (current leakage detection limit = 5 μA). In accordance with VDE 0884-2, each ADM2485 is proof tested by applying an insulation test voltage ≥1050 V discharge detection limit = 5 pC). ...
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... V = 500 sec, partial discharge < × 1 sec, partial discharge <5 pC IORM PR m × 1 sec, partial discharge <5 pC IORM PR m Rev Page ADM2485 Symbol Characteristic Unit III 40/85/ 560 V IORM PEAK V PR 1050 V PEAK 896 ...
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... Ground, Bus Side Power Supply, Bus Side (Isolated 5 V Supply) . Decoupling capacitor to GND DD2 be between 0.01 μF and 0.1 μ DD2 D2 GND GND GND ADM2485 DD1 TOP VIEW (Not to Scale) RxD GND RTS DE OUT 7 10 ...
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... Figure 8. RTS to DE OUT Propagation Delay A 110Ω TxD S1 50pF V B OUT RTS Figure 9. Driver Enable/Disable A V OUT Figure 10. Receiver Propagation Delay +1. –1. OUT RE IN Figure 11. Receiver Enable/Disable ADM2485 DE OUT 150Ω 50pF ...
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... ADM2485 SWITCHING CHARACTERISTICS 3V 1. PLH B 1/2VO – t SKEW PLH PHL 90% POINT VO 0V 10% POINT – Figure 12. Driver Propagation Delay, Rise/Fall Timing A – PLH RxD 1. SKEW PLH Figure 13. Receiver Propagation Delay 1.5V t PHL RTS | A – B 90% POINT 10% POINT A – B ...
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... DD2 –40 – TEMPERATURE (°C) Figure 20. Receiver Propagation Delay vs. Temperature CH1 2.0V Ω CH2 2.0V Ω M20.0ns 1.25GS/s CH3 2.0V Ω IT 8.0ps/pt Figure 21. Driver/Receiver Propagation Delay, Low to High ( Ω 100 pF) LDIFF L1 L2 ADM2485 CH3 2.60V ...
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... ADM2485 1 3 CH1 1.0V Ω CH2 1.0V Ω M10.0ns CH3 2.0V Ω T 19.8000ns Figure 22. Driver/Receiver Propagation Delay, High to Low ( Ω 100 pF) LDIFF L1 L2 350 300 250 SIDE 2 200 150 SIDE 1 100 100 CASE TEMPERATURE (°C) Figure 23. Thermal Derating Curve, Dependence of Safety-Limiting Values with Case Temperature per VDE 0884-2 – ...
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... CH1 2.0V Ω CH2 2.0V Ω M400ns 125MS/s = –4 mA) DD2 CH1 2.0V Ω CH2 2.0V Ω M80ns 625MS/s = –4 mA) DD2 (Break-Before-Make, 50 Ω Pull- Rev Page ADM2485 CH2 1.52V 8.0ns/pt Figure 28. Switching Waveforms (50 Ω Pull- and D2) DD1 CH2 1.52V 1 ...
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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 data enable, applied to the TxD and RTS pins, respectively, and referenced to logic ground ...
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... Therefore, iCouplers have essentially infinite dc field immunity. The following analysis defines the conditions under which this may occur. The ADM2485 3.3 V operating condition is examined, because it represents the most susceptible mode of operation. ...
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... V, ensuring enough headroom for the ADP3330 LDO to DD2 GND 2 output a regulated 5 V output. GND ADM2485 is powered the logic side, a 1CT:1.5CT A GND Transformer T1 is required, ensuring enough headroom for the 2 DE OUT ADP3330 LDO to output a regulated 5 V output. GND ...
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... COMPLIANT TO JEDEC STANDARDS MS-013- AA Figure 35. 16-Lead Standard Small Outline Package [SOIC_W] Wide Body (RW-16) Dimensions shown in millimeters and (inches) Temperature Range Package Description −40°C to +85°C 16-Lead SOIC_W −40°C to +85°C 16-Lead SOIC_W Rev Page ADM2485 45° 1.27 (0.0500) 0.40 (0.0157) Package Option RW-16 RW-16 ...
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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. D06021-0-1/07(0) Rev Page ...