MAX487 Maxim Integrated Products, MAX487 Datasheet
MAX487
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MAX487 Summary of contents
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... The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit. The MAX487 and MAX1487 feature quarter-unit-load receiver input impedance, allowing up to 128 MAX487/ MAX1487 transceivers on the bus. Full-duplex communi- cations are obtained using the MAX488–MAX491, while the MAX481, MAX483, MAX485, MAX487, and MAX1487 are designed for half-duplex applications ...
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... MAX487/MAX1487 V = 12V MAX487/MAX1487 0V 5.25V -7V IN -7V V 12V -4mA 200mV 4mA -200mV O ID 0.4V V 2.4V O -7V V 12V, all devices except CM MAX487/MAX1487 -7V V 12V, MAX487/MAX1487 CM MIN TYP MAX UNITS 1 0.2 V 2.0 V 0.8 V ±2 µA 1.0 mA -0.8 0.25 mA -0.2 -0.2 0 3.5 V 0.4 V ± ...
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... Figures 5 and 11 15pF, S1 closed LZ RL Figures 5 and 11 15pF, S2 closed HZ RL MAX481 (Note 5) MIN TYP MAX 120 250 300 500 500 900 CC 300 500 300 500 CC 230 400 MAX483 350 650 MAX487 250 400 120 250 0 250 35 250 7 95 MIN TYP MAX 100pF ...
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... S1 closed RL Figures 5 and 11 15pF, S2 closed < 50% of data period PLH PHL MAX483/MAX487 (Note 5) MAX483/MAX487, Figures 7 and 100pF, S2 closed L MAX483/MAX487, Figures 7 and 100pF, S1 closed L MAX483/MAX487, Figures 5 and 11 15pF, S2 closed L MAX483/MAX487, Figures 5 and 11 15pF, S1 closed L MIN TYP MAX UNITS 40 100 ns 40 100 ns 300 ...
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... Note 4: Applies to peak current. See Typical Operating Characteristics. Note 5: The MAX481/MAX483/MAX487 are put into shutdown by bringing RE high and DE low. If the inputs are in this state for less than 50ns, the parts are guaranteed not to enter shutdown. If the inputs are in this state for at least 600ns, the parts are guaranteed to have entered shutdown ...
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... DRIVER OUTPUT LOW VOLTAGE 140 120 100 OUTPUT LOW VOLTAGE (V) MAX483/MAX487–MAX489 SUPPLY CURRENT vs. TEMPERATURE 600 500 400 MAX483 300 MAX487 200 MAX483/MAX487 MAX488/MAX489 100 MAX483/MAX487 -50 -25 0 TEMPERATURE ( C) 6 _______________________________________________________________________________________ OUTPUT CURRENT vs. DRIVER OUTPUT HIGH VOLTAGE -120 -100 -80 -60 -40 - OUTPUT HIGH VOLTAGE (V) SUPPLY CURRENT vs ...
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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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... The 48k , 1 -unit-load receiver input impedance of the / 4 MAX487 and MAX1487 allows up to 128 transceivers on a bus, compared to the 1-unit load (12k impedance) of standard RS-485 drivers (32 trans- ceivers maximum). Any combination of MAX487/ MAX1487 and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481/MAX483/MAX485 and MAX488– ...
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... Figure 7. Driver Timing Test Load monics with large amplitudes are evident. Figure 13 shows the same information displayed for a MAX483, MAX487, MAX488, or MAX489 transmitting under the same conditions. Figure 13’s high-frequency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced. ...
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... Figure 9. Driver Enable and Disable Times (except MAX488 and MAX490 1. Figure 11. Receiver Enable and Disable Times (except MAX488 and MAX490) Table 2. Receiving OUTPUTS High High Don't care High-Z = High impedance * Shutdown mode for MAX481/MAX483/MAX487 1. ZL(SHDN) ZL 2.3V V +0.5V OUTPUT NORMALLY LOW OL OUTPUT NORMALLY HIGH V -0.5V 2. ZH(SHDN 1. ZL(SHDN ...
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... RE is high and DE is low for less than 50ns. If the inputs are in this state for at least 600ns, the parts are guaranteed to enter shutdown. For the MAX481, MAX483, and MAX487, the t t enable times assume the part was not in the low- ZL power shutdown state (the MAX485/MAX488– ...
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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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... MAX487CPA 0°C to +70°C MAX487CSA 0°C to +70°C MAX487CUA 0°C to +70°C MAX487C/D 0°C to +70°C MAX487EPA -40°C to +85°C MAX487ESA -40°C to +85°C MAX487MJA -55°C to +125°C MAX488CPA 0°C to +70°C MAX488CSA 0°C to +70°C MAX488CUA 0°C to +70°C MAX488C/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 ...