MAX485 Maxim Integrated Products, MAX485 Datasheet
MAX485
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MAX485 Summary of contents
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... EMI and reduce reflections caused by improperly terminated cables, thus allowing error-free data transmission up to 250kbps. The driver slew rates of the MAX481, MAX485, MAX490, MAX491, and MAX1487 are not limited, allowing them to transmit up to 2.5Mbps. These transceivers draw between 120µA and 500µA of supply current when unloaded or fully loaded with disabled drivers ...
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Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers ABSOLUTE MAXIMUM RATINGS Supply Voltage (V ) .............................................................12V CC Control Input Voltage (RE, DE)...................-0. Driver Input Voltage (DI).............................-0. Driver Output Voltage (A, B)...................................-8V to +12.5V Receiver Input Voltage (A, B).................................-8V to +12.5V ...
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... Supply Current in Shutdown I SHDN Driver Short-Circuit Current, I OSD1 V = High O Driver Short-Circuit Current, I OSD2 V = Low O Receiver Short-Circuit Current I OSR SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487 ( ±5 unless otherwise noted.) (Notes MIN MAX PARAMETER SYMBOL t PLH Driver Input to Output t PHL Driver Output Skew to Output ...
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... Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487 (continued ±5 unless otherwise noted.) (Notes MIN MAX PARAMETER SYMBOL Driver Enable from Shutdown to t ZH(SHDN) Output High (MAX481) Driver Enable from Shutdown to t ZL(SHDN) Output Low (MAX481) Receiver Enable from Shutdown ...
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NOTES FOR ELECTRICAL/SWITCHING CHARACTERISTICS Note 1: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless otherwise specified. Note 2: All typical specifications are given for V ...
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... OUTPUT HIGH VOLTAGE (V) SUPPLY CURRENT vs. TEMPERATURE 600 500 400 , MAX1487 300 , 200 MAX1487 0V 100 CC 0 -60 - 100 125 MAX481/MAX485/MAX490/MAX491 SUPPLY CURRENT vs. TEMPERATURE 600 MAX481/MAX485 500 400 300 MAX485 MAX481 200 MAX490/MAX491 100 MAX481 -50 - TEMPERATURE ( C) MAX1487 , - 100 120 140 TEMPERATURE ( C) 100 125 ...
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... MAX481 7 GND MAX483 MAX485 MAX487 MAX1487 MAX Figure 1. MAX481/MAX483/MAX485/MAX487/MAX1487 Pin Configuration and Typical Operating Circuit _______________________________________________________________________________________ Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers NAME MAX489/ NAME MAX491 DIP/SO Receiver Output > 200mV, RO will be high < 200mV, RO will be low. Receiver Output Enable enabled when RE is low high impedance when RE is high. ...
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... MAX483, MAX487, MAX488, and MAX489 are specified for data rates up to 250kbps. The MAX488–MAX491 are full-duplex trans- ceivers while the MAX481, MAX483, MAX485, MAX487, and MAX1487 are half-duplex. In addition, Driver Enable (DE) and Receiver Enable (RE) pins are included on the MAX481, MAX483, MAX485, MAX487, MAX489, MAX491, and MAX1487 ...
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... The MAX483 and MAX487–MAX489 are slew-rate limit- ed, minimizing EMI and reducing reflections caused by improperly terminated cables. Figure 12 shows the dri- ver output waveform and its Fourier analysis of a 150kHz signal transmitted by a MAX481, MAX485, MAX490, MAX491, or MAX1487. High-frequency har- _______________________________________________________________________________________ Low-Power, Slew-Rate-Limited ...
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... DIFF 90 SKEW = PLH PHL Figure 8. Driver Propagation Delays 1.5V V OUTPUT PHL PLH INPUT ID Figure 10. Receiver Propagation Delays _________________Function Tables (MAX481/MAX483/MAX485/MAX487/MAX1487) Table 1. Transmitting INPUTS High High Don't care High-Z = High impedance * Shutdown mode for MAX481/MAX483/MAX487 10 ______________________________________________________________________________________ 3V DE 1.5V 1.5V 0V 1/2 V ...
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... Figures 15–18 using Figure 14’s test circuit. ZH(SHDN) The difference in receiver delay times typically under 13ns for the MAX481, MAX485, MAX490, MAX491, and MAX1487 and is typically less than 100ns for the MAX483 and MAX487–MAX489. The driver skew times are typically 5ns (10ns max) for the MAX481, MAX485, MAX490, MAX491, and – ...
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... Figure 15. MAX481/MAX485/MAX490/MAX491/MAX1487 Receiver t PHL A 500mV/div B RO 2V/div 400ns/div Figure 17. MAX483, MAX487–MAX489 Receiver t 12 ______________________________________________________________________________________ 100pF Z B TTL < 6ns 100pF 500mV/div A 2V/div RO Figure 16. MAX481/MAX485/MAX490/MAX491/MAX1487 Receiver t PLH B 500mV/div + 2V/div RO Figure 18. MAX483, MAX487–MAX489 Receiver t PHL RECEIVER OUT + 20ns/div + 400ns/div PLH ...
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... RO RE MAX481 MAX483 MAX485 MAX487 MAX1487 Figure 21. MAX481/MAX483/MAX485/MAX487/MAX1487 Typical Half-Duplex RS-485 Network ______________________________________________________________________________________ Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers Figures 21 and 22 show typical network applications circuits. These parts can also be used as line repeaters, with cable lengths longer than 4000 feet, as shown in Figure 23. ...
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Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers A 120 120 NOTE: RE AND DE ON MAX489/MAX491 ONLY. Figure 22. MAX488–MAX491 Full-Duplex RS-485 Network MAX488–MAX491 A RO 120 ...
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... MAX485CPA 0°C to +70°C MAX485CSA 0°C to +70°C MAX485CUA 0°C to +70°C MAX485C/D 0°C to +70°C MAX485EPA -40°C to +85°C MAX485ESA -40°C to +85°C MAX485MJA -55°C to +125°C MAX487CPA 0°C to +70°C MAX487CSA 0°C to +70°C MAX487CUA 0°C to +70°C MAX487C/D 0° ...
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Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers _____________________________________________Chip Topographies (continued) MAX488/MAX490 N.C. N.C. DI GND 0.080" (2.032mm) 16 ______________________________________________________________________________________ 0.054" Z (1.372mm TRANSISTOR COUNT: 248 SUBSTRATE CONNECTED TO GND MAX489/MAX491 ...
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For the latest package outline information go to www.maxim-ic.com/packages.) ______________________________________________________________________________________ Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers Package Information 17 ...
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Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 18 ______________________________________________________________________________________ Package Information (continued) ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 19 © 2003 Maxim Integrated Products ...