View MAX487_4005008.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. general description the max481, max483, max485, MAX487?ax491, and max1487 are low-power transceivers for rs-485 and rs- 422 communication. each part contains one driver and one receiver. the max483, MAX487, max488, and max489 feature reduced slew-rate drivers that minimize 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 120? and 500? of supply current when unloaded or fully loaded with disabled drivers. additionally, the max481, max483, and MAX487 have a low-current shutdown mode in which they consume only 0.1?. all parts operate from a single 5v supply. drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-imped- ance state. 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?ax491, while the max481, max483, max485, MAX487, and max1487 are designed for half-duplex applications. ________________________applications low-power rs-485 transceivers low-power rs-422 transceivers level translators transceivers for emi-sensitive applications industrial-control local area networks ____________________________features in ?ax package: smallest 8-pin so slew-rate limited for error-free data transmission (max483/487/488/489) 0.1?low-current shutdown mode (max481/483/487) low quiescent current: 120? (max483/487/488/489) 230? (max1487) 300? (max481/485/490/491) -7v to +12v common-mode input voltage range three-state outputs 30ns propagation delays, 5ns skew (max481/485/490/491/1487) full-duplex and half-duplex versions available operate from a single 5v supply allows up to 128 transceivers on the bus (MAX487/max1487) current-limiting and thermal shutdown for driver overload protection ordering information ordering information continued at end of data sheet. * contact factory for dice specifications. max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers ________________________________________________________________ maxim integrated products 1 ______________________________________________________________selection table 19-0122; rev 7; 6/03 part temp range pin-package max481 cpa 0? to +70? 8 plastic dip max481csa 0? to +70? 8 so max481cua 0? to +70? 8 ?ax max481c/d 0? to +70? dice* max481 max483 max485 MAX487 max488 max489 max490 max491 max1487 part number half/full duplex data rate (mbps) slew-rate limited low-power shutdown receiver/ driver enable quiescent current ( a) number of transmitters on bus pin count half half half half full full full full half 2.5 0.25 2.5 0.25 0.25 0.25 2.5 2.5 2.5 no yes no yes yes yes no no no yes yes no yes no no no no no yes yes yes yes no yes no yes yes 300 120 300 120 120 120 300 300 230 32 32 32 128 32 32 32 32 128 8 8 8 8 8 14 8 14 8
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 2 _______________________________________________________________________________________ absolute maximum ratings supply voltage (v cc ) .............................................................12v control input voltage ( re , de)...................-0.5v to (v cc + 0.5v) driver input voltage (di).............................-0.5v to (v cc + 0.5v) driver output voltage (a, b)...................................-8v to +12.5v receiver input voltage (a, b).................................-8v to +12.5v receiver output voltage (ro).....................-0.5v to (v cc +0.5v) continuous power dissipation (t a = +70 c) 8-pin plastic dip (derate 9.09mw/ c above +70 c) ....727mw 14-pin plastic dip (derate 10.00mw/ c above +70 c) ..800mw 8-pin so (derate 5.88mw/ c above +70 c).................471mw 14-pin so (derate 8.33mw/ c above +70 c)...............667mw 8-pin max (derate 4.1mw/ c above +70 c) ..............830mw 8-pin cerdip (derate 8.00mw/ c above +70 c).........640mw 14-pin cerdip (derate 9.09mw/ c above +70 c).......727mw operating temperature ranges max4_ _c_ _/max1487c_ a ...............................0 c to +70 c max4_ _e_ _/max1487e_ a .............................-40 c to +85 c max4_ _mj_/max1487mja ...........................-55 c to +125 c storage temperature range .............................-65 c to +160 c lead temperature (soldering, 10sec) .............................+300 c dc electrical characteristics (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v v in = -7v v in = 12v v in = -7v v in = 12v input current (a, b) i in2 v th k ? 48 -7v v cm 12v, MAX487/max1487 r in receiver input resistance -7v v cm 12v, all devices except MAX487/max1487 r = 27 ? (rs-485), figure 4 0.4v v o 2.4v r = 50 ? (rs-422) i o = 4ma, v id = -200mv i o = -4ma, v id = 200mv v cm = 0v -7v v cm 12v de, di, re de, di, re MAX487/max1487, de = 0v, v cc = 0v or 5.25v de, di, re r = 27 ? or 50 ? , figure 4 r = 27 ? or 50 ? , figure 4 r = 27 ? or 50 ? , figure 4 de = 0v; v cc = 0v or 5.25v, all devices except MAX487/max1487 conditions k ? 12 a 1 i ozr three-state (high impedance) output current at receiver v 0.4 v ol receiver output low voltage 3.5 v oh receiver output high voltage mv 70 ? v th receiver input hysteresis v -0.2 0.2 receiver differential threshold voltage -0.2 ma 0.25 ma -0.8 1.0 1.5 5 v od2 differential driver output (with load) v 2 v 5 v od1 differential driver output (no load) a 2 i in1 input current v 0.8 v il input low voltage v 2.0 v ih input high voltage v 0.2 ? v od change in magnitude of driver common-mode output voltage for complementary output states v 0.2 ? v od change in magnitude of driver differential output voltage for complementary output states v 3 v oc driver common-mode output voltage units min typ max symbol parameter
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers _______________________________________________________________________________________ 3 switching characteristics?ax481/max485, max490/max491, max1487 (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) dc electrical characteristics (continued) (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) ma 795 0v v o v cc i osr receiver short-circuit current ma 35 250 -7v v o 12v (note 4) i osd2 driver short-circuit current, v o = low ma 35 250 -7v v o 12v (note 4) i osd1 driver short-circuit current, v o = high max1487, re = 0v or v cc 250 400 350 650 ns 10 30 60 t phl driver rise or fall time figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf ns max490m, max491m max490c/e, max491c/e 20 90 150 max481, max485, max1487 max490m, max491m max490c/e, max491c/e max481, max485, max1487 figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf max481 (note 5) figures 5 and 11, c rl = 15pf, s2 closed figures 5 and 11, c rl = 15pf, s1 closed figures 5 and 11, c rl = 15pf, s2 closed figures 5 and 11, c rl = 15pf, s1 closed figures 6 and 10, r diff = 54 ? , c l1 = c l2 = 100pf figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf figures 6 and 10, r diff = 54 ? , c l1 = c l2 = 100pf conditions ns 510 t skew ns 50 200 600 t shdn time to shutdown mbps 2.5 f max maximum data rate ns 20 50 t hz receiver disable time from high ns 10 30 60 t plh 20 50 t lz receiver disable time from low ns 20 50 t zh driver input to output receiver enable to output high ns 20 50 t zl receiver enable to output low 20 90 200 ns ns 13 40 70 t hz t skd driver disable time from high | t plh - t phl | differential receiver skew ns 40 70 t lz driver disable time from low ns 40 70 t zl driver enable to output low 31540 ns 51525 ns 31540 t r , t f 20 90 200 driver output skew to output t plh , t phl receiver input to output 40 70 t zh driver enable to output high units min typ max symbol parameter conditions units min typ max symbol parameter 230 400 300 500 max481/max485, re = 0v or v cc 500 900 max490/max491, de, di, re = 0v or v cc 300 500 max488/max489, de, di, re = 0v or v cc 120 250 de = v cc 300 500 de = 0v de = v cc de = 0v a max481/483/487, de = 0v, re = v cc 0.1 10 i shdn supply current in shutdown 120 250 i cc no-load supply current (note 3) de = 5v de = 0v max483 MAX487 max483/MAX487, re = 0v or v cc figures 7 and 9, c l = 100pf, s2 closed figures 7 and 9, c l = 100pf, s1 closed figures 7 and 9, c l = 15pf, s1 closed figures 7 and 9, c l = 15pf, s2 closed a
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 4 _______________________________________________________________________________________ switching characteristics?ax483, MAX487/max488/max489 (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) switching characteristics?ax481/max485, max490/max491, max1487 (continued) (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) 300 1000 figures 7 and 9, c l = 100pf, s2 closed figures 7 and 9, c l = 100pf, s1 closed figures 5 and 11, c l = 15pf, s2 closed, a - b = 2v conditions ns 40 100 t zh(shdn) driver enable from shutdown to output high (max481) ns figures 5 and 11, c l = 15pf, s1 closed, b - a = 2v t zl(shdn) receiver enable from shutdown to output low (max481) ns 40 100 t zl(shdn) driver enable from shutdown to output low (max481) ns 300 1000 t zh(shdn) receiver enable from shutdown to output high (max481) units min typ max symbol parameter t plh t skew figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf t phl figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf driver input to output driver output skew to output ns 100 800 ns ns 2000 max483/MAX487, figures 7 and 9, c l = 100pf, s2 closed t zh(shdn) driver enable from shutdown to output high 250 2000 ns 2500 max483/MAX487, figures 5 and 11, c l = 15pf, s1 closed t zl(shdn) receiver enable from shutdown to output low ns 2500 max483/MAX487, figures 5 and 11, c l = 15pf, s2 closed t zh(shdn) receiver enable from shutdown to output high ns 2000 max483/MAX487, figures 7 and 9, c l = 100pf, s1 closed t zl(shdn) driver enable from shutdown to output low ns 50 200 600 max483/MAX487 (note 5) t shdn time to shutdown t phl t plh , t phl < 50% of data period figures 5 and 11, c rl = 15pf, s2 closed figures 5 and 11, c rl = 15pf, s1 closed figures 5 and 11, c rl = 15pf, s2 closed figures 5 and 11, c rl = 15pf, s1 closed figures 7 and 9, c l = 15pf, s2 closed figures 6 and 10, r diff = 54 ? , c l1 = c l2 = 100pf figures 7 and 9, c l = 15pf, s1 closed figures 7 and 9, c l = 100pf, s1 closed figures 7 and 9, c l = 100pf, s2 closed conditions kbps 250 f max 250 800 2000 maximum data rate ns 20 50 t hz receiver disable time from high ns 250 800 2000 20 50 t lz receiver disable time from low ns 20 50 t zh receiver enable to output high ns 20 50 t zl receiver enable to output low ns ns 100 300 3000 t hz t skd driver disable time from high i t plh - t phl i differential receiver skew figures 6 and 10, r diff = 54 ? , c l1 = c l2 = 100pf ns 300 3000 t lz driver disable time from low ns 250 2000 t zl driver enable to output low ns figures 6 and 8, r diff = 54 ? , c l1 = c l2 = 100pf ns 250 2000 t r , t f 250 2000 driver rise or fall time ns t plh receiver input to output 250 2000 t zh driver enable to output high units min typ max symbol parameter
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers _______________________________________________________________________________________ 5 30 0 02.5 output current vs. receiver output low voltage 5 25 max481-01 output low voltage (v) output current (ma) 1.5 15 10 0.5 1.0 2.0 20 35 40 45 0.9 0.1 -50 -25 25 75 receiver output low voltage vs. temperature 0.3 0.7 temperature ( c) output low voltage (v) 050 0.5 0.8 0.2 0.6 0.4 0 100 125 max481-04 i ro = 8ma -20 -4 1.5 2.0 3.0 5.0 output current vs. receiver output high voltage -8 -16 max481-02 output high voltage (v) output current (ma) 2.5 4.0 -12 -18 -6 -14 -10 -2 0 3.5 4.5 4.8 3.2 -50 -25 25 75 receiver output high voltage vs. temperature 3.6 4.4 temperature ( c) output high voltage (v) 050 4.0 4.6 3.4 4.2 3.8 3.0 100 125 max481-03 i ro = 8ma 90 0 0 1.0 3.0 4.5 driver output current vs. differential output voltage 10 70 max481-05 differential output voltage (v) output current (ma) 2.0 4.0 50 30 80 60 40 20 0.5 1.5 2.5 3.5 2.3 1.5 -50 -25 25 125 driver differential output voltage vs. temperature 1.7 2.1 max481-06 temperature ( c) differential output voltage (v) 075 1.9 2.2 1.6 2.0 1.8 100 50 2.4 r = 54 ? __________________________________________typical operating characteristics (v cc = 5v, t a = +25 c, unless otherwise noted.) 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 cc = 5v and t a = +25 c. note 3: supply current specification is valid for loaded transmitters when de = 0v. 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. see low-power shutdown mode section.
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 6 _______________________________________________________________________________________ ____________________________typical operating characteristics (continued) (v cc = 5v, t a = +25 c, unless otherwise noted.) 120 0 08 output current vs. driver output low voltage 20 100 max481-07 output low voltage (v) output current (ma) 6 60 40 24 80 10 12 140 -120 0 -7 -5 -1 5 output current vs. driver output high voltage -20 -80 max481-08 output high voltage (v) output current (ma) -3 1 -60 3 -6 -4 -2 0 2 4 -100 -40 100 -40 -60 -20 40 100 120 max1487 supply current vs. temperature 300 max481-13 temperature ( c) supply current ( a) 20 60 80 500 200 600 400 0 0 140 max1487; de = v cc , re = x max1487; de = 0v, re = x 100 -50 -25 50 100 max481/max485/max490/max491 supply current vs. temperature 300 max481-11 temperature ( c) supply current ( a) 25 75 500 200 600 400 0 0 125 max481/max485; de = v cc , re = x max485; de = 0, re = x, max481; de = re = 0 max490/max491; de = re = x max481; de = 0, re = v cc 100 -50 -25 50 100 max483/MAX487?ax489 supply current vs. temperature 300 max481-12 temperature ( c) supply current ( a) 25 75 500 200 600 400 0 0 125 max483; de = v cc , re = x MAX487; de = v cc , re = x max483/MAX487; de = 0, re = v cc max483/MAX487; de = re = 0, max488/max489; de = re = x
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers _______________________________________________________________________________________ 7 ______________________________________________________________pin description max481 max483 max485 MAX487 max1487 top view note: pin labels y and z on timing, test, and waveform diagrams refer to pins a and b when de is high. typical operating circuit shown with dip/so package. 1 2 3 4 8 5 v cc gnd di de re ro r d rt rt 7 6 d r de re di ro a b 1 2 3 4 8 7 6 5 v cc b a gnd di de re ro dip/so r d 1 2 3 4 8 7 6 5 v cc a gnd de re b ro max b a di max481 max483 max485 MAX487 max1487 figure 1. max481/max483/max485/MAX487/max1487 pin configuration and typical operating circuit max 5 6 7 8 2 1 3 max 4 5 6 7 8 1 2 dip/so dip/so 2 3 receiver output enable. ro is enabled when re is low; ro is high impedance when re is high. 3 4 driver output enable. the driver outputs, y and z, are enabled by bringing de high. they are high impedance when de is low. if the driver outputs are enabled, the parts function as line drivers. while they are high impedance, they function as line receivers if re is low. dip/so 4 5 driver input. a low on di forces output y low and output z high. similarly, a high on di forces output y high and output z low. 5 6, 7 ground 9 noninverting driver output 10 inverting driver output 3 4 6 noninverting receiver input and noninverting driver output 12 noninverting receiver input 5 6 8 re de di gnd y z a a 7 b inverting receiver input and inverting driver output 7 11 b inverting receiver input 8 1 14 v cc positive supply: 4.75v v cc 5.25v 1, 8, 13 n.c. no connect not internally connected function name 4 3 1 2 receiver output: if a > b by 200mv, ro will be high; if a < b by 200mv, ro will be low. 2 ro pin function name max481/max483/ max485/MAX487/ max1487 max488/ max490 max489/ max491
max481/max483/max485/MAX487?ax491/max1487 __________applications information the max481/max483/max485/MAX487 max491 and max1487 are low-power transceivers for rs-485 and rs- 422 communications. the max481, max485, max490, max491, and max1487 can transmit and receive at data rates up to 2.5mbps, while the 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. when disabled, the driver and receiver outputs are high impedance. MAX487/max1487: 128 transceivers on the bus the 48k ? , 1 / 4 -unit-load receiver input impedance of the MAX487 and max1487 allows up to 128 transceivers on a bus, compared to the 1-unit load (12k ? input 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 max491 have standard 12k ? receiver input impedance. low-power, slew-rate-limited rs-485/rs-422 transceivers 8 _______________________________________________________________________________________ max488 max490 top view 1 2 3 4 ro di gnd 8 7 6 5 a b z y v cc dip/so r d rt rt v cc 5 6 7 8 ro di gnd 4 gnd di ro 3 2 a b y z v cc dr r d 1 3 v cc 4 ro 2 a 1 6 5 7 8 gnd di y z b max max488 max490 note: typical operating circuit shown with dip/so package. max489 max491 dip/so top view rt rt de v cc re gnd v cc re gnd de ro di 9 10 12 11 b a z y 5 ro nc di 2 1, 8, 13 3 6, 7 14 4 1 2 3 4 5 6 7 14 13 12 11 10 9 8 v cc n.c. n.c. a b z y n.c. ro re de di gnd gnd r d d rd r figure 2. max488/max490 pin configuration and typical operating circuit figure 3. max489/max491 pin configuration and typical operating circuit
max483/MAX487/max488/max489: reduced emi and reflections 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- 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. max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers _______________________________________________________________________________________ 9 r r y z v od v oc receiver output test point 1k ? 1k ? s1 s2 v cc c rl 15pf di de 3v y z c l1 c l2 a b ro re r diff v id output under test 500 ? s1 s2 v cc c l _________________________________________________________________test circuits figure 4. driver dc test load figure 5. receiver timing test load figure 6. driver/receiver timing test circuit figure 7. driver timing test load
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 10 ______________________________________________________________________________________ _______________________________________________________switching waveforms di 3v 0v z y v o 0v -v o v o 1.5v t plh 1/2 v o 10% t r 90% 90% t phl 1.5v 1/2 v o 10% t f v diff = v (y) - v (z) v diff t skew = | t plh - t phl | output normally low output normally high 3v 0v y, z v ol y, z 0v 1.5v 1.5v v ol +0.5v v oh -0.5v 2.3v 2.3v t zl(shdn) , t zl t lz t zh(shdn) , t zh t hz de v oh v ol v id -v id 1.5v 0v 1.5v output input 0v ro a-b t plh t phl output normally low output normally high 3v 0v v cc ro ro 0v 1.5v 1.5v v ol + 0.5v v oh - 0.5v 1.5v 1.5v t zl(shdn) , t zl t lz t zh(shdn) , t zh t hz re _________________function tables (max481/max483/max485/MAX487/max1487) figure 8. driver propagation delays figure 9. driver enable and disable times (except max488 and max490) figure 10. receiver propagation delays figure 11. receiver enable and disable times (except max488 and max490) table 1. transmitting table 2. receiving inputs output re de a-b ro 0 0 0 1 0 0 0 0 > +0.2v < -0.2v inputs open x 1 0 1 high-z * x = don't care high-z = high impedance * shutdown mode for max481/max483/MAX487 inputs outputs re de di z y x x 0 1 1 1 0 0 1 0 x x 0 1 high-z high-z * 1 0 high-z high-z * x = don't care high-z = high impedance * shutdown mode for max481/max483/MAX487
low-power shutdown mode (max481/max483/MAX487) a low-power shutdown mode is initiated by bringing both re high and de low. the devices will not shut down unless both the driver and receiver are disabled. in shutdown, the devices typically draw only 0.1a of supply current. re and de may be driven simultaneously; the parts are guaranteed not to enter shutdown if 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 zh and t zl enable times assume the part was not in the low- power shutdown state (the max485/max488 max491 and max1487 can not be shut down). the t zh(shdn) and t zl(shdn) enable times assume the parts were shut down (see electrical characteristics ). it takes the drivers and receivers longer to become enabled from the low-power shutdown state (t zh(shdn ), t zl(shdn) ) than from the operating mode (t zh , t zl ). (the parts are in operating mode if the r e , de inputs equal a logical 0,1 or 1,1 or 0, 0.) driver output protection excessive output current and power dissipation caused by faults or by bus contention are prevented by two mechanisms. a foldback current limit on the output stage provides immediate protection against short cir- cuits over the whole common-mode voltage range (see typical operating characteristics ). in addition, a ther- mal shutdown circuit forces the driver outputs into a high-impedance state if the die temperature rises excessively. propagation delay many digital encoding schemes depend on the differ- ence between the driver and receiver propagation delay times. typical propagation delays are shown in figures 15 18 using figure 14 s test circuit. the difference in receiver delay times, | t plh - t phl |, is 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 max1487, and are typically 100ns (800ns max) for the max483 and MAX487 max489. max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers ______________________________________________________________________________________ 11 10db/div 0hz 5mhz 500khz/div 10db/div 0hz 5mhz 500khz/div figure 12. driver output waveform and fft plot of max481/ max485/max490/max491/max1487 transmitting a 150khz signal figure 13. driver output waveform and fft plot of max483/ MAX487?ax489 transmitting a 150khz signal
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 12 ______________________________________________________________________________________ ttl in t r , t f < 6ns d r 100pf b 100pf a receiver out r = 54 ? z y 500mv/div 20ns/div a b ro 2v/div v cc = 5v t a = +25 c 500mv/div 20ns/div a b ro 2v/div v cc = 5v t a = +25 c 500mv/div 400ns/div a b ro 2v/div v cc = 5v t a = +25 c 500mv/div 400ns/div a b ro 2v/div v cc = 5v t a = +25 c figure 14. receiver propagation delay test circuit figure 15. max481/max485/max490/max491/max1487 receiver t phl figure 16. max481/max485/max490/max491/max1487 receiver t plh figure 17. max483, MAX487?ax489 receiver t phl figure 18. max483, MAX487?ax489 receiver t plh
line length vs. data rate the rs-485/rs-422 standard covers line lengths up to 4000 feet. for line lengths greater than 4000 feet, see figure 23. figures 19 and 20 show the system differential voltage for the parts driving 4000 feet of 26awg twisted-pair wire at 110khz into 120 ? loads. typical applications the max481, max483, ma x485, MAX487 max491, and max1487 transceivers are designed for bidirectional data communications on multipoint bus transmission lines. 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. to minimize reflections, the line should be terminated at both ends in its characteristic impedance, and stub lengths off the main line should be kept as short as possi- ble. the slew-rate-limited max483 and MAX487 max489 are more tolerant of imperfect termination. max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers ______________________________________________________________________________________ 13 di v y -v z ro 5v 0v 1v 0v -1v 5v 0v 2 s/div di v y -v z ro 5v 0v 1v 0v -1v 5v 0v 2 s/div di ro de re a b re re re ro ro ro di di di de de de d d d r r r bb b a a a 120 ? 120 ? d r max481 max483 max485 MAX487 max1487 figure 19. max481/max485/max490/max491/max1487 system differential voltage at 110khz driving 4000ft of cable figure 20. max483, MAX487?ax489 system differential voltage at 110khz driving 4000ft of cable figure 21. max481/max483/max485/MAX487/max1487 typical half-duplex rs-485 network
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 14 ______________________________________________________________________________________ figure 22. max488?ax491 full-duplex rs-485 network 120 ? 120 ? r d ro re de di a b y 120 ? 120 ? di di di ro ro ro de de de re re re z z z z y y y aa a bb b d d d r r r max489 max491 note: re and de on max489/max491 only. figure 23. line repeater for max488?ax491 120 ? 120 ? data in data out r d ro re de di a b z y max488?ax491 note: re and de on max489/max491 only. isolated rs-485 for isolated rs-485 applications, see the max253 and max1480 data sheets.
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers ______________________________________________________________________________________ 15 __ordering information (continued) _________________chip topographies max481/max483/max485/MAX487/max1487 n.c. ro 0.054" (1.372mm) 0.080" (2.032mm) de di gnd b n.c. v cc a re * contact factory for dice specifications. 14 cerdip -55 c to +125 c max489mjd 14 so -40 c to +85 c max489esd 14 plastic dip -40 c to +85 c max489epd dice* 0 c to +70 c max489c/d 14 so 0 c to +70 c max489csd 14 plastic dip 0 c to +70 c max489 cpd 8 cerdip -55 c to +125 c max488mja 8 so -40 c to +85 c max488esa 8 plastic dip -40 c to +85 c max488epa dice* 0 c to +70 c max488c/d 8 so 0 c to +70 c max488csa 8 plastic dip 0 c to +70 c max488 cpa 8 cerdip -55 c to +125 c MAX487mja 8 so -40 c to +85 c MAX487esa 8 plastic dip -40 c to +85 c MAX487epa dice* 0 c to +70 c MAX487c/d 8 so 0 c to +70 c MAX487csa 8 plastic dip 0 c to +70 c MAX487 cpa 8 cerdip -55 c to +125 c max485mja 8 so -40 c to +85 c max485esa 8 plastic dip -40 c to +85 c max485epa dice* 0 c to +70 c max485c/d 8 so 0 c to +70 c max485csa 8 plastic dip 0 c to +70 c max485 cpa 8 cerdip -55 c to +125 c max483mja 8 so -40 c to +85 c max483esa 8 plastic dip -40 c to +85 c max483epa 8 cerdip -55 c to +125 c max481mja 8 plastic dip -40 c to +85 c max481epa pin-package temp. range part 14 cerdip -55 c to +125 c max491mjd 14 so -40 c to +85 c max491esd 14 plastic dip -40 c to +85 c max491epd dice* 0 c to +70 c max491c/d 14 so 0 c to +70 c max491csd 14 plastic dip 0 c to +70 c max491 cpd 8 cerdip -55 c to +125 c max490mja 8 so -40 c to +85 c max490esa 8 plastic dip -40 c to +85 c max490epa dice* 0 c to +70 c max490c/d 8 plastic dip 0 c to +70 c max490 cpa pin-package temp. range part 8 so -40 c to +85 c max481esa 8 max 0 c to +70 c max485cua 8 max 0 c to +70 c MAX487cua 8 max 0 c to +70 c max488cua 8 so 0 c to +70 c max490csa 8 max 0 c to +70 c max490cua __ordering information (continued) 8 cerdip -55 c to +125 c max1487mja 8 so -40 c to +85 c max1487esa 8 plastic dip -40 c to +85 c max1487epa dice* 0 c to +70 c max1487c/d 8 so 0 c to +70 c max1487csa 8 plastic dip 0 c to +70 c max1487 cpa 8 max 0 c to +70 c max1487cua 8 max 0 c to +70 c max483cua dice* 0 c to +70 c max483c/d 8 so 0 c to +70 c max483csa 8 plastic dip 0 c to +70 c max483 cpa
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 16 ______________________________________________________________________________________ transistor count: 248 substrate connected to gnd max488/max490 b ro 0.054" (1.372mm) 0.080" (2.032mm) n.c. di gnd z a v cc y n.c. _____________________________________________chip topographies (continued) max489/max491 b ro 0.054" (1.372mm) 0.080" (2.032mm) de di gnd z a v cc y re
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers ______________________________________________________________________________________ 17 package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .) soicn .eps package outline, .150" soic 1 1 21-0041 b rev. document control no. approval proprietary information title: top view front view max 0.010 0.069 0.019 0.157 0.010 inches 0.150 0.007 e c dim 0.014 0.004 b a1 min 0.053 a 0.19 3.80 4.00 0.25 millimeters 0.10 0.35 1.35 min 0.49 0.25 max 1.75 0.050 0.016 l 0.40 1.27 0.394 0.386 d d mindim d inches max 9.80 10.00 millimeters min max 16 ac 0.337 0.344 ab 8.75 8.55 14 0.189 0.197 aa 5.004.80 8 n ms012 n side view h 0.2440.228 5.80 6.20 e 0.050 bsc 1.27 bsc c h e e b a1 a d 0-8 l 1 variations:
max481/max483/max485/MAX487?ax491/max1487 low-power, slew-rate-limited rs-485/rs-422 transceivers 18 ______________________________________________________________________________________ 8lumaxd.eps package outline, 8l umax/usop 1 1 21-0036 j rev. document control no. approval proprietary information title: max 0.043 0.006 0.014 0.120 0.120 0.198 0.026 0.007 0.037 0.0207 bsc 0.0256 bsc a2 a1 c e b a l front view side view e h 0.60.1 0.60.1 ? 0.500.1 1 top view d 8 a2 0.030 bottom view 1 6 s b l h e d e c 0 0.010 0.116 0.116 0.188 0.016 0.005 8 4x s inches - a1 a min 0.002 0.950.75 0.5250 bsc 0.25 0.36 2.95 3.05 2.95 3.05 4.78 0.41 0.65 bsc 5.03 0.66 60 0.13 0.18 max min millimeters - 1.10 0.05 0.15 dim package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .)
max481/max483/max485/MAX487?ax491 low-power, slew-rate-limited rs-485/rs-422 transceivers 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 printed usa is a registered trademark of maxim integrated products. max481/max483/max485/MAX487?ax491/max1487 pdipn.eps package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .)

▲Up To Search▲

Price & Availability of MAX487

	To Download MAX487 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .