1 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation sp481e/sp485e features +5v only low power bicmos driver/receiver enable for multi-drop configurations low power shutdown mode ( sp481e ) enhanced esd specifications: +15kv human body model +15kv iec1000-4-2 air discharge +8kv iec1000-4-2 contact discharge enhanced low power half-duplex rs-485 transceivers r d ro 1 re 2 de 3 di 4 8 vcc 7 b 6 a 5 gnd sp481e and sp485e the sp481e and the sp485e are a family of half-duplex transceivers that meet the specifications of rs-485 and rs-422 serial protocols with enhanced esd performance. the esd tolerance has been improved on these devices to over + 15kv for both human body model and iec1000-4-2 air discharge method. these devices are pin-to-pin compatible with sipex's sp481 and sp485 devices as well as popular industry standards. as with the original versions, the sp481e and the sp485e feature sipex's bicmos design allowing low power operation without sacrificing performance. the sp481e and sp485e meet the requirements of the rs-485 and rs-422 protocols up to 10mbps under load. the sp481e is equipped with a low power shutdown mode. description sp481e and sp485e pinout (top view) ro 1 re 2 de 3 di 4 8 v cc 7 b 6 a 5 gnd d r sp485 top view now available in lead free packaging
date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation 2 absolute maximum ratings these are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. exposure to absolute maximum rating conditions for extended periods of time may affect reliability. v cc ..........................................................................................................+7v input voltages logic........................................................-0.3v to (v cc +0.5v) drivers..................................................-0.3v to (v cc +0.5v) receivers................................................................. 15v t min to t max and v cc = 5v 5% unless otherwise noted. parameters min. typ. max. units conditions sp481e/sp485e driver dc characteristics differential output voltage gnd v cc volts unloaded; r = ; see figure 1 differential output voltage 2 v cc volts with load; r = 50 ? ; (rs-422); see figure 1 differential output voltage 1.5 v cc volts with load; r = 27 ? ; (rs-485); see figure 1 change in magnitude of driver differential output voltage for complimentary states 0.2 volts r = 27 ? or r = 50 ? ; see figure 1 driver common-mode output voltage 3 volts r = 27 ? or r = 50 ? ; see figure 1 input high voltage 2.0 volts applies to de, di, re input low voltage 0.8 volts applies to de, di, re input current 10 a applies to de, di, re driver short-circuit current v out = high 250 ma -7v v o +12v v out = low 250 ma -7v v o +12v sp481e/sp485e driver ac characteristics maximum data rate 10 mbps re = 5v, de = 5v; r diff = 54 ? , c l1 = c l2 = 100pf driver input to output 20 30 60 ns t plh ; r diff = 54 ? , c l1 = c l2 = 100pf; see figures 3 and 5 driver input to output 20 30 80 ns t plh ; r diff = 54 ? , c li = c l2 = 100pf; (sp485emn only) see figures 3 and 5 driver input to output 20 30 60 ns t phl ; r diff = 54 ? , c l1 = c l2 = 100pf; see figures 3 and 5 driver input to output 20 30 80 ns t phl ; r diff = 54 ? , c l1 = c l2 = 100pf; (sp485emn only) see figures 3 and 5 driver skew 5 10 ns see figures 3 and 5, t skew = | t dplh - t dphl | driver rise or fall time 3 15 40 ns from 10% to 90%; r diff = 54 ? , c l1 = c l2 = 100pf; s ee figures 3 & 6 driver enable to output high 40 70 ns c l = 100pf; see figures 4 & 6; s 2 closed driver enable to output low 40 70 ns c l = 100pf; see figures 4 & 6; s 1 closed driver disable time from low 40 70 ns c l = 100pf; see figures 4 & 6; s 1 closed driver disable time from high 40 70 ns c l = 100pf; see figures 4 & 6; s 2 closed output voltages logic........................................................-0.3v to (v cc +0.5v) drivers...................................................................... 15v receivers............................................-0.3v to (v cc +0.5v) storage temperature.......................................................-65?c to +150?c power dissipation per package 8-pin nsoic (derate 6.60mw/ o c above +70 o c)...........................550mw 8-pin pdip (derate 11.8mw/ o c above +70 o c)............................1000mw electrical characteristics
3 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation t min to t max and v cc = 5v 5% unless otherwise noted. parameters min. typ. max. units conditions sp481e/sp485 e receiver dc characteristics differential input threshold -0.2 +0.2 volts -7v v cm +12v differential input threshold -0.4 +0.4 volts -7v v cm +12v (sp485emn only) input hysteresis 20 mv v cm = 0v output voltage high 3.5 volts i o = -4ma, v id = +200mv output voltage low 0.4 volts i o = +4ma, v id = -200mv three-state (high impedance) output current 1 a 0.4v v o 2.4v; re = 5v input resistance 12 15 k ? -7v v cm +12v input current (a, b); v in = 12v +1.0 ma de = 0v, v cc = 0v or 5.25v, v in = 12v input current (a, b); v in = -7v -0.8 ma de = 0v, v cc = 0v or 5.25v, v in = -7v short-circuit current 7 95 ma 0v v o v cc sp481e/sp485e receiver ac characteristics maximum data rate 10 mbps re = 0v, de = 0v receiver input to output 20 45 100 ns t plh ; r diff = 54 ? , c l1 = c l2 = 100pf; figures 3 & 7 receiver input to output 20 45 100 ns t phl ; r diff = 54 ? , c l1 = c l2 = 100pf; figures 3 & 7 diff. receiver skew it plh -t phl i13 nsr diff = 54 ? ; c l1 = c l2 = 100pf; figures 3 & 7 receiver enable to output low 45 70 ns c rl = 15pf; figures 2 & 8; s 1 closed receiver enable to output high 45 70 ns c rl = 15pf; figures 2 & 8; s 2 closed receiver disable from low 45 70 ns c rl = 15pf; figures 2 & 8; s 1 closed receiver disable from high 45 70 ns c rl = 15pf; figures 2 & 8; s 2 closed sp481e shutdown timing time to shutdown 50 200 600 ns re = 5v, de = 0v driver enable from shutdown to output high 40 100 ns c l = 100pf; see figures 4 & 6; s 2 closed driver enable from shutdown to output low 40 100 ns c l = 100pf; see figures 4 & 6; s 1 closed receiver enable from shutdown to output high 300 1000 ns c l = 15pf; see figures 2 & 8; s 2 closed receiver enable from shutdown to output low 300 1000 ns c l = 15pf; see figures 2 & 8; s 1 closed power requirements supply voltage +4.75 +5.25 volts supply current sp481e/485e no load 900 a re, di = 0v or v cc ; de = v cc 600 a re = 0v, di = 0v or 5v; de = 0v sp481e shutdown mode 10 a de = 0v, re=v cc environmental and mechanical operating temperature commercial (_c_) 0 +70 c industrial (_e_) -40 +85 c (_m_) -40 +125 c storage temperature -65 +150 c package plastic dip (_p) nsoic (_n) electrical characteristics
date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation 4 pin function pin 1 ?ro ?receiver output. pin 2 ?re ?receiver output enable active low. pin 3 ?de ?driver output enable active high. pin 4 ?di ?driver input. pin 5 ?gnd ?ground connection. pin 6 ?a ?driver output/receiver input non-inverting. pin 7 ?b ?driver output/receiver input inverting. pin 8 ?vcc ?positive supply 4.75v 5 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation inputs outputs line re de di condition b a x1 1 no fault 0 1 x1 0 no fault 1 0 x0x x zz x1x fau lt z z inputs outputs re de a - b r 00 +0.2v 1 00 -0.2v 0 00 inputs open 1 10 x z table 1. transmit function truth table table 2. receive function truth table +3v 0v de 5v v ol a, b 0v 1.5v 1.5v t zl t zh f = 1mhz; t r < 10ns; t f < 10ns v oh a, b 2.3v 2.3v t lz t hz 0.5v 0.5v output normally low output normally high +3v 0v re 5v r 0v 1.5v 1.5v t zl t zh f = 1mhz; t r < 10ns; t f < 10ns r 1.5v 1.5v t lz t hz 0.5v 0.5v output normally low output normally high v il v ih figure 8. receiver enable and disable times figure 7. receiver propagation delays figure 6. driver enable and disable times v oh v ol r 1.5v 1.5v t phl f = 1mhz; t r < 10ns; t f < 10ns output v 0d2 + v 0d2 a ?b 0v 0v t plh input t skew = | t phl - t plh |
date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation 6 receivers the sp481e and sp485e receivers have differ- ential inputs with an input sensitivity as low as 200mv. input impedance of the receivers is typically 15k ? (12k ? minimum). a wide com- mon mode range of -7v to +12v allows for large ground potential differences between systems. the receivers of the sp481e and sp485e have a tri-state enable control pin. a logic low on re (pin 2) will enable the receiver, a logic high on re (pin 2) will disable the receiver. the receiver for the sp481e and sp485e will operate up to at least 10mbps. the receiver for each of the two devices is equipped with the fail-safe feature. fail-safe guarantees that the receiver output will be in a high state when the input is left unconnected. shutdown mode sp481e the sp481e is equipped with a shutdown mode. to enable the shutdown state, both the driver and receiver must be disabled simultaneously. a logic low on de (pin 3) and a logic high on re (pin 2) will put the sp481e into shutdown mode. in shutdown, supply current will drop to typically 1 a. esd tolerance the sp481e family incorporates ruggedized esd cells on all driver output and receiver input pins. the esd structure is improved over our previous family for more rugged applications and environments sensitive to electro-static dis- charges and associated transients. the improved esd tolerance is at least 15kv without damage nor latch-up. there are different methods of esd testing applied: a) mil-std-883, method 3015.7 b) iec1000-4-2 air-discharge c) iec1000-4-2 direct contact description the sp481e and sp485e are half-duplex differ- ential transceivers that meet the requirements of rs-485 and rs-422. fabricated with a sipex proprietary bicmos process, all three products require a fraction of the power of older bipolar designs. the rs-485 standard is ideal for multi-drop applications and for long-distance interfaces. rs-485 allows up to 32 drivers and 32 receivers to be connected to a data bus, making it an ideal choice for multi-drop applications. since the cabling can be as long as 4,000 feet, rs-485 transceivers are equipped with a wide (-7v to +12v) common mode range to accommodate ground potential differences. because rs-485 is a differential interface, data is virtually immune to noise in the transmission line. drivers the driver outputs of the sp481e and sp485e are differential outputs meeting the rs-485 and rs-422 standards. the typical voltage output swing with no load will be 0 volts to +5 volts. with worst case loading of 54 ? across the differ- ential outputs, the drivers can maintain greater than 1.5v voltage levels. the drivers of the sp481e , and sp485e have an enable control line which is active high. a logic high on de (pin 3) will enable the differential driver outputs. a logic low on de (pin 3) will tri-state the driver outputs. the transmitters of the sp481e and sp485e will operate up to at least 10mbps.
7 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation the human body model has been the generally accepted esd testing method for semiconductors. this method is also specified in mil-std-883, method 3015.7 for esd testing. the premise of this esd test is to simulate the human body? potential to store electro-static energy and discharge it to an integrated circuit. the simulation is performed by using a test model as shown in figure 7 . this method will test the ic? capability to withstand an esd transient during normal handling such as in manufacturing areas where the ics tend to be handled frequently. the iec-1000-4-2, formerly iec801-2, is generally used for testing esd on equipment and systems. for system manufacturers, they must guarantee a certain amount of esd protection since the system itself is exposed to the outside environment and human presence. the premise with iec1000-4-2 is that the system is required to withstand an amount of static electricity when esd is applied to points and surfaces of the equipment that are accessible to personnel during normal usage. the transceiver ic receives most of the esd current when the esd source is applied to the connector pins. the test circuit for iec1000-4-2 is shown on figure 8 . there are two methods within iec1000-4-2, the air discharge method and the contact discharge method. r r c c c c s s r r s s sw1 sw1 sw2 sw2 r c device under t est dc power source c s r s sw1 sw2 figure 7. esd test circuit for human body model r r s s and and r r v v add up to 330 add up to 330 ? ? f f or iec1000-4-2. or iec1000-4-2. r s and r v add up to 330 ? for iec1000-4-2. contact-discharge module contact-discharge module r r v v r r c c c c s s r r s s sw1 sw1 sw2 sw2 r c device under t est dc power source c s r s sw1 sw2 r v contact-discharge module figure 8. esd test circuit for iec1000-4-2
date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation 8 with the air discharge method, an esd voltage is applied to the equipment under test (eut) through air. this simulates an electrically charged person ready to connect a cable onto the rear of the system only to find an unpleasant zap just before the person touches the back panel. the high energy potential on the person discharges through an arcing path to the rear panel of the system before he or she even touches the system. this energy, whether discharged directly or through air, is predominantly a function of the discharge current rather than the discharge voltage. variables with an air discharge such as approach speed of the object carrying the esd potential to the system and humidity will tend to change the discharge current. for example, the rise time of the discharge current varies with the approach speed. the contact discharge method applies the esd current directly to the eut. this method was devised to reduce the unpredictability of the esd arc. the discharge current rise time is constant since the energy is directly transferred without the air-gap arc. in situations such as hand held systems, the esd charge can be directly discharged to the equipment from a person already holding the equipment. the current is transferred on to the keypad or the serial port of the equipment directly and then travels through the pcb and finally to the ic. the circuit model in figures 7 and 8 represent the typical esd testing circuit used for all three methods. the c s is initially charged with the dc power supply when the first switch (sw1) is on. now that the capacitor is charged, the second switch (sw2) is on while sw1 switches off. the voltage stored in the capacitor is then applied through r s , the current limiting resistor, onto the device under test (dut). in esd tests, the sw2 switch is pulsed so that the device under test receives a duration of voltage. for the human body model, the current limiting resistor (r s ) and the source capacitor (c s ) are 1.5k ? an 100pf, respectively. for iec-1000-4- 2, the current limiting resistor (r s ) and the source capacitor (c s ) are 330 ? an 150pf, respectively. the higher c s value and lower r s value in the iec1000-4-2 model are more stringent than the human body model. the larger storage capacitor injects a higher voltage to the test point when sw2 is switched on. the lower current limiting resistor increases the current charge onto the test point. figure 9. esd test waveform for iec1000-4-2 t=0ns t=30ns 0a 15a 30a t ? i ? human body iec1000-4-2 model air discharge direct contact level driver outputs 15kv 15kv 8kv 4 receiver inputs 15kv 15kv 8kv 4 sp481e, sp485e family
9 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation package: 8 pin pdip index area b n 1 23 n/2 c d1 ea eb e symbol min nom max a--0 .21 a1 0.15 - - a2 0.115 0.13 0.195 b0. 014 0.018 0.022 b2 0.045 0.06 0.07 b3 0.3 0.039 0.045 c0. 008 0.01 0.014 d0. 355 0.365 0.4 d1 0.005 - - e0.30. 31 0.325 e1 0.24 0.25 0.28 e ea eb - - 0.43 l0. 115 0.13 0.15 note: dimensions in (mm) .100 bsc .300 bsc 8 pin pdip jedec ms-001 (ba) variation e e1 d a l a2 a1 b b2 e b3 c
date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation 10 package: 8 pin nsioc a a1 a2 side view seating plane section b-b with plating symbol min nom max a 1.35 - 1.75 a1 0.1 - 0.25 a2 1.25 - 1.65 b 0.31 - 0.51 c 0.17 - 0.24 d e e1 e l 0.4 - 1.27 l1 l2 ?0o-8o ?1 5o - 15o note: dimensions in (mm) 8 pin nsoic jedec mo-012 (aa) variation 4.90 bsc 6.00 bsc 3.90 bsc 1.27 bsc 1.04 ref 0.25 bsc gauge plane l1 l 1 seating plane l2 view c to p view b see view c b b e e/2 e1 index area (d/2 x e1/2) e1/2 d 1 e c base metal b
11 date: 02/24/05 sp481e low power half-duplex rs485 transceivers ?copyright 2005 sipex corporation corporation analog excellence sipex corporation reserves the right to make changes to any products described herein. sipex does not assume any liability aris ing out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor t he rights of others. sipex corporation headquarters and sales office 233 south hillview drive milpitas, ca 95035 tel: (408) 934-7500 fax: (408) 935-7600 ordering information part number top mark temperature range package sp481ecn ................................. 481ecnyywwh................0?c to +70?c ................................... 8-pin nsoic sp481ecn/tr ............................ 481ecnyywwh................0?c to +70?c ................................... 8-pin nsoic sp481ecp .................................. sp481ecpyyww..............0?c to +70?c ...................................... 8-pin pdi p sp481een ................................. .481eenyyww................-40?c to +85?c .................................. 8-pin nsoic sp481een/tr ........................... .481eenyyww................-40?c to +85?c .................................. 8-pin nsoic sp481eep ................................. sp481eepyyww............-40?c to +85?c ..................................... 8-pin pdip sp485ecn ................................. 485ecnyyww...................0?c to +70?c ................................... 8-pin nsoi c sp485ecn/tr ............................ 485ecnyyww...................0?c to +70?c ................................... 8-pin nsoic sp485ecp ................................. sp485ecpyyww...............0?c to +70?c ..................................... 8-pin pdip sp485een ................................ 485ecnyyww...................-40?c to +85?c ................................. 8-pin nsoic sp485een/tr .......................... 485ecnyyww...................-40?c to +85?c ................................. 8-pin nsoic sp485eep ................................ sp485eepyyww...............-40?c to +85?c .................................... 8-pin pdip sp485emn ............................. sp485emnyyww................-40?c to +125?c ............................... 8-pin nsoic sp485emn/tr ....................... sp485emnyyww................-40?c to +125?c ............................... 8-pin nsoic /tr = tape and reel pack quantity is 2500 for narrow soic. available in lead free packaging. to order add "-l" suffix to part number. example: sp485een/tr = standard; sp485een-l/tr = lead free click here to order samples
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