technical data 2012 , february , v e r . 0 2 low - power, slew - rate - limited rs - 485/rs - 422 transceivers description the ilx485 is low - power transceivers for rs - 485 and rs - 422 communication. ic contains one driver and one receiver. the driver slew rates of the ilx485 is not limited, allowing th em to transmit up to 10 mbps. these transceivers draw between 120a and 500a of supply current when unloaded or fully loaded with disabled drivers. all parts operate from a single 5v supply. drivers are short - circuit current limited and are protected agai nst excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high - impedance state. the receiver input has a fail - safe feature that guarantees a logic - high output if the input is open circuit. the ilx485 is designed fo r half - duplex applications. ILX485N dip 8 ilx485d sop 8 features ? low quiescent current: 300a ? - 7v to +12v common - mode input voltage range ? three - state outputs ? 5 0ns propagation delays, 5ns skew ? full - duplex and half - duplex v ersions available ? operate from a single 5v supply ? allows up to 32 transceivers on the bus ? data rate: 10 mbps ? current - limiting and thermal shutdown for driver overload protection ? enhanced esd specifications: 15kv iec 6 1000 - 4 - 2 air discharge 8kv iec 6 1000 - 4 - 2 contact discharge pin d escription ilx 485 ordering information device operating temperature range package shipping ILX485N t a = - 40 ? to 85 ? c dip8 tube ilx485d sop8 tube ilx485dt sop8 t ape & reel free datasheet http:///
ilx485 2012 , february , v e r . 0 2 absolute maximum ratings supply voltage (v cc ) 12v continuous power dissipation (t a = +70c) control input voltage - 0.5v to (v cc + 0.5v) 8 - pin plastic dip (derate 9.09mw/c above +70c) 727mw driver input voltage (di) - 0.5v to (v c c + 0.5v) 8 - pin so p (derate 5.88mw/c above +70c) 471mw driver output voltage (a, b) - 8v to +12.5v operating temperature ranges - 40 c to + 85 c receiver input voltage (a, b) - 8v to +12.5v storage temperature range - 65c to +160c receiver output voltage (ro) - 0.5v to (v cc +0.5v) lead temperature (soldering, 10sec) +300c * stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. these are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. exposure to absolute - maximum - rated conditions for extended periods may affect device reliability. dc electrical characteristics (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) parameter symbol conditions min typ max units differential driver output (no loa d) v od1 5 v differential driver output (with load) v od2 r = 50 ? od r = 27 oc r = 27 ? od r = 27 ih de, di, re 2.0 v input low voltage v il de, di, re 0.8 v input current i in1 de, di, re 2 a in2 de = 0v; v in = 12v 1.0 ma v cc = 0v or 5.25v v in = - 7v - 0.8 receiver differential threshold voltage v th - 7v v cm 12v ? th v cm = 0v 70 mv receiver output high voltage v oh i o = - 4ma, vid = 200mv 3.5 v receiver output low voltage v ol i o = 4ma, vid = - 200mv 0.4 v three - state (high impedance) output current at receiver i ozr 0.4v v o 2.4v 1 a in - 7v v cm 12v k free datasheet http:///
ilx485 2012 , february , v e r . 0 2 dc electrical characteristics (continue) (vcc = 5v 5%, t a = tmin to tmax, unless otherwise noted.) (notes 1, 2) parameter symbol conditions min typ max units no - load supply current (note 3) i cc de = v cc 500 900 re = 0v or v cc 300 500 a de = 0v driver short - circuit current i osd1 - 7v v o 12v (note 4) 35 250 ma vo = high driver short - circuit current i osd2 - 7v v o 12v (note 4) 35 250 ma vo = low receiver short - circuit current i osr 0 v v o v cc 7 95 ma esd protection a, b, y and z pins, tested using human body model ? 15 kv switching characteristics (v cc = 5v 5%, t a = t min to t max , unless otherwise noted.) (notes 1, 2) parameter symbol conditions min typ max units driver i nput to output t plh r diff = 54 ? 10 55 60 ns t phl c l1 = c l2 = 100pf 10 55 60 driver output skew to output t skew r diff = 54 ? , c l1 = c l2 = 100pf 5 10 ns driver enable to output high t zh c l = 100pf, s2 closed 40 70 ns driver enable to output low t zl c l = 100pf, s1 closed 40 70 ns driver disable time from low t lz c l = 15pf, s1 closed 40 70 ns driver disable time from high t hz c l = 15pf, s2 closed 40 70 ns receiver input to output t plh r diff = 54 ? c l1 = c l2 = 100pf 20 60 100 ns t phl 20 60 100 | t pl h - t phl | differential receiver skew t skd r diff = 54 ? c l1 = c l2 = 100pf 5 10 ns receiver enable to output low t zl c rl = 15pf, s1 closed 3 0 50 ns receiver enable to output high t zh c rl = 15pf, s2 closed 3 0 50 ns receiver disable time from low t lz c rl = 15pf, s1 closed 3 0 50 ns receiver disable time from high t hz c rl = 15pf, s2 closed 3 0 50 ns maximum data rate f max 2.5 10 20 mbps note 1: all currents into device pins are positive; all currents out of device pins are negative. all voltages are r eferenced 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. free datasheet http:///
ilx485 2012 , february , v e r . 0 2 test circuits figure 1 . driver v od and v oc figure 2 . driver v od with varying common - mode voltage figure 3 . receiver v oh and v ol figure 4 . driver differential output delay and transition times free datasheet http:///
ilx485 2012 , february , v e r . 0 2 test circuits (continue) figure 5 . driver propagation times figure 6 . driver enable and disable times (t pzh , t psh , t phz ) figure 7 . driver enable and disable times (t pzl , t psl , t plz ) free datasheet http:///
ilx485 2012 , february , v e r . 0 2 test circuits (continue) figure 8 . receiver propagation delay figure 9 . receiver ena ble and disable times note 5: the input pulse is supplied by a generator with the following characteristics: prr = 250khz, 50% duty cycle, tr ? 6.0ns, z o = 50 . note 6: c l includes probe and stray capacitance. free datasheet http:///
ilx485 2012 , february , v e r . 0 2 function tables transmi tting inputs outputs x re de di z y x 1 1 0 1 x 1 0 1 0 0 0 x z z 1 0 x z z x - dont care z - high impedance recei ving inputs outputs re de a - b ro 0 0 +0.2v 1 0 0 - 0.2v 0 0 0 open 1 1 0 x z typical information figure 10. ilx485 typical rs - 485 network 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 circuits over the whole common - mode voltage range. in addition, a thermal shutdown circuit forces the driver outputs into a high - impedance state if the die temperature rises exce ssively. propagation delay skew time is simply the difference between the low - to - high and high - to - low propagation delay. small driver/receiver skew times help maintain a symmetrical mark - space ratio (50% duty cycle). the receiver skew time, | t prlh - t prhl | , is under 10ns. the driver skew times are 5 ns for the ilx 485 . typical applications ilx485 transceivers are designed for bidirectional data communications on multipoint bus transmission lines. figure 10 show s typical network applications circuits. these parts can also be used as line repeaters, with cable lengths longer than 4000 feet. 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 possible . free datasheet http:///
ilx485 2012 , february , v e r . 0 2 package dimensions n suffix plastic dip (ms C 001ba) symbol min max a 8.51 10.16 b 6.1 7.11 c 5.33 d 0.36 0.56 f 1.14 1.78 g h j 0 10 k 2.92 3.81 notes: l 7.62 8.26 1. ???? dimensions a, b do not include mold flash or protrusions. m 0.2 0.36 maximum mold flash or protrusions 0.25?mm (0.010) per side. n 0.38 d suffix soic (ms - 012aa) symbol min max a 4.8 5 b 3.8 4 c 1.35 1.75 d 0.33 0.51 f 0.4 1.27 g h j 0 8 notes: k 0.1 0.25 1. ???? dimensions a and b do not include mold flash or protrusion. m 0.19 0.25 2. ???? maximum mold flash or protrusion 0.15?mm (0.006) per side p 5.8 6.2 for a; for b ? 0.25?mm (0.010) per side. r 0.25 0.5 1.27 5.72 dimension, mm dimension, mm 2.54 7.62 a b h c k c m j f m p g d r x 45 seating plane 0.25 (0.010) m t -t- 1 8 4 5 l h m j a b f g d seating plane n k 0.25 (0.010) m t -t- c 1 8 4 5 free datasheet http:///
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