* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download MAX13085EASA+中文资料
Survey
Document related concepts
Integrating ADC wikipedia , lookup
Power MOSFET wikipedia , lookup
Regenerative circuit wikipedia , lookup
Valve RF amplifier wikipedia , lookup
Immunity-aware programming wikipedia , lookup
Wilson current mirror wikipedia , lookup
Voltage regulator wikipedia , lookup
Surge protector wikipedia , lookup
Transistor–transistor logic wikipedia , lookup
Resistive opto-isolator wikipedia , lookup
Power electronics wikipedia , lookup
Schmitt trigger wikipedia , lookup
Operational amplifier wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Current mirror wikipedia , lookup
Transcript
文档下载 免费文档下载 http://doc.wendoc.com/ MAX13085EASA+中文资料 本文档下载自文档下载网,内容可能不完整,您可以复制以下网址继续阅读或下载: http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html 19-3590; Rev 1; 4/05 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers General Description Features The MAX13080E–MAX13089E 5.0V, ±15kV ESD-protect-ed, RS-485/RS-422 transceivers feature one driver and? 5.0V Operation one receiver. These devices include fail-safe circuitry,?Extended ESD Protection for RS-485/RS-422 I/O Pins guaranteeing a logic-high receiver output when receiver±15kV Human Body Modelinputs are open or shorted. The receiver outputs a logic-high if all transmitters on a terminated bus are disabled?True Fail-Safe Receiver While Maintaining(high impedance). The MAX13080E–MAX13089E includeEIA/TIA-485 Compatibility a hot-swap capability to eliminate false transitions on the?Hot-Swap Input Structures on DE and REbus during power-up or hot insertion. The MAX13080E/MAX13081E/MAX13082E feature?Enhanced Slew-Rate Limiting Facilitates Error-reduced slew-rate drivers that minimize EMI andFree 文档下载 免费文档下载 http://doc.wendoc.com/ http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlData Transmission reduce reflections caused terminated(MAX13080E–MAX13085E/MAX13089E)cables, transmission up to?Low-Current Shutdown by improperly allowing Mode error-free data (Except250kbps. The MAX13083E/MAX13084E/MAX13085EMAX13081E/MAX13084E/MAX13087E)also slew-rate-limited drivers but allow transmitspeeds up to feature 500kbps. The MAX13086E/MAX13087E/?Pin-Selectable Full-/Half-Duplex OperationMAX13088E driver slew rates are not limited, making(MAX13089E)transmit speeds up to 16Mbps possible. TheMAX13089E slew rate is pin selectable for 250kbps,?Phase Controls to Correct for Twisted-Pair500kbps, and 16Mbps. Reversal (MAX13089E)The MAX13082E/MAX13085E/MAX13088E are intended?Allow Up to 256 Transceivers on the Busfor half-duplex communications, and the MAX13080E/?Available in Industry-Standard 8-Pin SO Package MAX13081E/MAX13083E/MAX13084E/MAX13086E/MAX13087E are intended for full-duplex communica-tions. http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlThe MAX13089E is selectable for half-duplex orfull-duplex operation. It also features independentlyprogrammable receiver and transmitter output phasethrough separate pins. Ordering Information The MAX13080E–MAX13089E transceivers draw 1.2mAof supply current when unloaded or when fully loadedwith the drivers disabled. All devices have a 1/8-unitload receiver input impedance, allowing up to 256transceivers on the bus. The MAX13080E/MAX13083E/MAX13086E/MAX13089Eare available in 14-pin PDIP and 14-pin SO packages.The MAX13081E/MAX13082E/MAX13084E/MAX13085E/MAX13087E/MAX13088E are 文档下载 免费文档下载 http://doc.wendoc.com/ available in 8-pin PDIP and8-pin SO packages. The devices operate over the com-mercial, extended, and automotive temperature ranges. Applications Ordering Information continued at end of data sheet. Utility MetersLighting SystemsIndustrial ControlSelector Guide, Pin Configurations, and Typical OperatingCircuithttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmls appear at end of data sheet. TelecomSecurity SystemsInstrumentationProfibus ________________________________________________________________Maxim Integrated Products1 For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E ABSOLUTE MAXIMUM RATINGS (All Voltages Referenced to GND) Supply Voltage (VCC)............................................................. 6VControl Input Voltage (RE, DE, SLR, 文档下载 免费文档下载 http://doc.wendoc.com/ H/F, TXP, RXP)......................................................-0.3V to 6VDriver Input Voltage (DI)...........................................-0.3V to 6VDriver Output Voltage (Z, Y, A, B).............................-8V to 13VReceiver Input Voltage http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html(A, B)....................................-8V to Full Duplex (A, 13VReceiver Input Voltage B)..................................................-8V 13VReceiver Output Voltage (RO)....................-0.3V to (VCC to 0.3V)Driver Output Current.....................................................±250mA Continuous Power Dissipation (TA= 70°C) 8-Pin SO (derate 5.88mW/°C above 70°C).................471mW8-Pin Plastic DIP (derate 9.09mW/°C above 70°C).....727mW14-Pin SO (derate 8.33mW/°C above 70°C)...............667mW14-Pin Plastic DIP (derate 10.0mW/°C above 70°C)...800mWOperating Temperature Ranges MAX1308_EC_ _.................................................0°C MAX1308_EE_ 85°CMAX1308_EA_ to 75°C _..............................................-40°C to _............................................-40°C to 125°CJunction Temperature...................................................... 150°CSthttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlorage Range.............................-65°C to Temperature 150°CLead Temperature (soldering, 10s)................................. 300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating 文档下载 免费文档下载 http://doc.wendoc.com/ conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) (Note 1) 2_______________________________________________________________________________ ________ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers DC ELECTRICAL CHARACTERISTICS (continued) ://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html(VCC= unless otherwise noted. Typical values are at VCC= 5.0V ±10%, TA= TMINto TMAX, 5.0V and TA= 25°C.) (Note 1) ________________________________________________________________________________ _______3 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E DRIVER SWITCHING CHARACTERISTICS MAX13080E/MAX13081E/MAX13082E/MAX13089E WITH SRL = UNCONNECTED (250kbps) (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) 文档下载 免费文档下载 http://doc.wendoc.com/ RECEIVER SWITCHING CHARACTERISTICS MAX13080E/MAX13081E/MAX13082E/MAX13089E WITHSRL = UNCONNECTED (250kbps) (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) 4_______________________________________________________________________________ ________ 5.0V, ±http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers DRIVER SWITCHING CHARACTERISTICS MAX13083E/MAX13084E/MAX13085E/MAX13089E WITHSRL = VCC(500kbps) (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) RECEIVER SWITCHING CHARACTERISTICS MAX13083E/MAX13084E/MAX13085E/MAX13089E WITHSRL = VCC(500kbps) (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) ________________________________________________________________________________ _______5 文档下载 免费文档下载 http://doc.wendoc.com/ MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E DRIVER SWITCHING CHARACTERISTICS MAX13086E/MAX13087E/MAX13088E/MAX13089E WITHSRL = GND (16Mbps) (VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlical values are at VCC= 5.0V and TA= 25°C.) RECEIVER SWITCHING CHARACTERISTICS MAX13086E/MAX13087E/MAX13088E/MAX13089E WITHSRL = GND (16Mbps) (VCC= VCC= 5.0V ±10%, TA= TMINto TMAX, unless otherwise noted. Typical values are at 5.0V and TA= 25°C.) Note 2:?VODand ?VOCare the changes in VODand VOC, respectively, when the DI input changes state. Note 3:The short-circuit output current applies to peak current just prior to foldback current limiting. The short-circuit foldback output current applies during current limiting to allow a recovery from bus contention.6 ________________________________________________________________________________ 文档下载 免费文档下载 http://doc.wendoc.com/ _______ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers (VCC= 5.0V, TA = 25°C, unless otherwise noted.) OUTPUT CURRENT OUTPUT CURRENT SUPPLY CURRENT vs. TEMPERAhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlTURE vs. RECEIVER OUTPUT-HIGH VOLTAGE vs. RECEIVER OUTPUT-LOW VOLTAGE 1.60602 0703 0ccoott EE1.50998-50E0608-E088003311)) X) XA1.40AAAAmmMm50M((( TT40TN1.30NNEEERRR40RRRUUC1.20UC YTTLUU30PPP1.10USTU20PTUOO1.00200.9010100.80 C30 文档下载 免费文档下载 http://doc.wendoc.com/ -40-25-105203550658095110125 012345012345 TEMPERATURE (°C) OUTPUT HIGH VOLTAGE (V)OUTPUT LOW VOLTAGE (V) RECEIVER OUTPUT-HIGH VOLTAGE RECEIVER OUTPUT-LOW VOLTAGE DRIVER DIFFERENTIAL OUTPUT CURRENTvs. TEMPERATURE vs. TEMPERATURE vs. DIFFERENTIAL OUTPUT VOLTAGE 5.40.8160 0.7)A5.2m140( ) ) VT(VN( E 0.6EG5.0ER120AGRTAULTC 100OL0.5TV4.8OU TLUUAPP0.3I60TTU4.4TUNO0.2EORE40F4.2F0.1ID204.0 0-40-25-105203550658095110125 VH PGWTIO0.4U80HLO T4.6 文档下载 免费文档下载 http://doc.wendoc.com/ -40-25-1052035506580951101250 1 2 ://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlar3 4 5 TEMPERATURE (°C) TEMPERATURE (°C) DIFFERENTIAL OUTPUT VOLTAGE (V) DRIVER DIFFERENTIAL OUTPUTOUTPUT CURRENT vs. TRANSMITTER OUTPUT CURRENT vs. TRANSMITTER VOLTAGE vs. TEMPERATURE OUTPUT-HIGH VOLTAGE OUTPUT-LOW VOLTAGE 4.8200 文档下载 免费文档下载 http://doc.wendoc.com/ 200180) 180V(4.4 E160G160A) ) TAAL4.0Omm140(140(V TT TNNUEE120 P3.6R120RTRRUUUC100OC100 LTTA3.2UUIP80P80TNTTEUUR2.8O60O60EFFI4040D2.420 202.0 -40-25-10 5203550658095110125-7-6-5-4-3 -2-10 1 2 34 5 文档下载 免费文档下载 http://doc.wendoc.com/ 024681012 TEMPERATURE (°C) OUTPUT HIGH VOLTAGE (V) OUTPUT-LOW VOLTAGE (V) ________________________________________________________________________________ _______7 MAX13080E–MAX13089E 5.0V, ±15kV Failhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html-Safe, RS-485/RS-422 TransceiversMAX13080E–MAX13089E (VCC= 5.0V, TA = 25°C, unless otherwise noted.) SHUTDOWN CURRENTvs. TEMPERATURE 9SHUTDOWN CURRENT (?A) 876543210 -40-25-10 5203550658095110125TEMPERATURE (°C) 600 ESD-Protected, Hot-Swap, 文档下载 免费文档下载 http://doc.wendoc.com/ -40-25-10 5203550658095110125TEMPERATURE (°C) 300 -40-25-105203550658095110125 TEMPERATURE (°C) MAX13080E-89E toc10 DRIVER PROPAGATION DELAYvs. TEMPERATURE (250kbps) DRIVER PROPAGATION DELAYvs. TEMPERATURE (500kbps) 101200DRIVER PROPAGATION DELAY (ns)1100 1000900800700 600DRIVER PROPAGATION DELAY (ns) 550500450400350 DRIVER PROPAGATION DELAYvs. TEMPERATURE (16Mbps) RECEIVER PROPAGATION DELAY vs. TEMPERATURE (250kpbs AND 500kbps) 文档下载 免费文档下载 http://doc.wendoc.com/ RECEIVER PROPAGATION DELAY (ns) 160140120100806040200 -40-25-1http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html0 5203550658095110125TEMPERATURE (°C) RECEIVER PROPAGATION DELAYvs. TEMPERATURE (16Mbps) 180REC EIVER PROPAGA TION DELAY (ns) 160140120100806040200 -40-25-105203550658095110125 TEMPERATURE (°C) 80 DRIVER PROPAGATION DELAY (ns) 706050403020100 -40-25-10 文档下载 免费文档下载 http://doc.wendoc.com/ 180 5203550658095110125TEMPERATURE (°C) DRIVER PROPAGATION DELAY (250kbps) RECEIVER PROPAGATION DELAY (250kbps AND 500kbps) DI2V/div VA - VB5V/div VY - VZ5V/div RO2V/div 2?s/div200ns/div 8_______________________________________________________________________________ ________ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers (VCC= 5.0V, TA = 25°C, unless otherwise noted.) DRIVER PROPAGATION DELAY (500kbps) 文档下载 免费文档下载 http://doc.wendoc.com/ DRIVER PROPAGAThttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlION DELAY (16Mbps) RECEIVER PROPAGATION DELAY (16Mbps) VBDIDI2V/div 2V/div 2V/div VAV2V/div Z2V/div VY - VZ5V/div ROVY2V/div 2V/div 400ns/div 10ns/div40ns/div Figure 2. Driver Timing Test Circuit ________________________________________________________________________________ _______9 文档下载 免费文档下载 http://doc.wendoc.com/ MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E Figure 4. Driver Enable and Disable Times (tDHZ, tDZH, tDZH(SHDN)) DZLDLZDLZ(SHDN)10 ________________________________________________________________________________ ______ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers Figure 6. Receiver Propagation Delay Test Circuit _____________________________________________________________http://doc.wendoc.c om/b2be828f3f110692c7ce0fc0d.html_________________________ 11 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers Function Tables 文档下载 免费文档下载 http://doc.wendoc.com/ MAX13080E/MAX13083E/MAX13086E MAX13081E/MAX13084E/MAX13086E/MAX13087E ________________________________________________________________________________ ______13 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E Function Tables (continued) MAX13082E/MAX13085E/MAX13088E MAX13089E 14______________________________________________________________________________ ________ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers than or equal to -200mV, RO is cahttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlse logic-low. of In the aThe MAX13080E–MAX13089E high-speed transceiversterminated bus with all transmitters disabled, the receiv-for RS-485/RS-422 communication contain one driverer’s differential input voltage is pulled to 0V by the termi-and one receiver. These devices feature fail-safe circuit-nation. With the receiver thresholds of the 文档下载 免费文档下载 http://doc.wendoc.com/ MAX13080Ery, which guarantees a logic-high receiver output whenfamily, this results in a logic-high with a 50mV minimumthe receiver inputs are open or shorted, or when they arenoise margin. Unlike previous fail-safe devices, theconnected to a terminated transmission line with all dri--50mV to -200mV threshold complies with the ±200mVvers disabled (see the Fail-Safesection). TheEIA/TIA-485 standard. MAX13080E/MAX13082E/MAX13083E/MAX13085E/MAX13086E/MAX13088E/MAX13089E also feature a hot-Hot-Swap Capability (Except swap capability allowing line insertion without erroneousMAX13081E/MAX13084E/MAX13087Ehttp://doc.wendoc.com/b2be828f3f110692c7ce 0fc0d.html) data transfer (see the Hot Swap Capabilitysection). TheHot-Swap Inputs MAX13080E/MAX13081E/MAX13082E feature reducedWhen circuit boards are inserted into a hot or poweredslew-rate drivers that minimize EMI and reduce reflec-backplane, differential disturbances to the data bustions caused by improperly terminated cables, allowingcan lead to data errors. Upon initial circuit board inser-error-free data transmission up to 250kbps. Thetion, the data communication processor undergoes itsMAX13083E/MAX13084E/MAX13085E also offer slew-own power-up sequence. During this period, therate limits allowing transmit speeds up to 500kbps. Theprocessor’s logic-output drivers are high impedanceMAX13086E/MAX13087E/MAX13088Es’ driver slew ratesand are unable to drive the DE and REinputs of theseare not limited, making transmit speeds up to 16Mbpsdevices to a defined logic level. Leakage currents up topossible. The MAX13089E’s slew rathttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmle is selectable±10?A from the high-impedance state of the proces-between 250kbps, 500kbps, and 16Mbps by driving asor’s logic drivers could cause standard CMOS enableselector pin with a three-state driver. 文档下载 免费文档下载 http://doc.wendoc.com/ inputs of a transceiver to drift to an incorrect logic level.The MAX13082E/MAX13085E/MAX13088E are half-Additionally, parasitic circuit board capacitance couldduplex transceivers, while the MAX13080E/MAX13081E/cause coupling of VCCor GND to the enable inputs.MAX13083E/MAX13084E/MAX13086E/MAX13087E areWithout the hot-swap capability, these factors couldfull-duplex transceivers. The MAX13089E is selectableimproperly enable the transceiver’s driver or receiver. between half- and full-duplex communication by drivingWhen Va selector pin (H/F) high or low, respectively. low and CCrises, an internal pulldown circuit holds DEREhigh. After the initial power-up sequence,All devices operate from a single 5.0V supply. Drivershttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlthe pulldown circuit becomes transparent, resetting theare output short-circuit current limited. Thermal-shutdownhot-swap tolerable input. circuitry protects drivers against excessive power dissi-Hot-Swap Input Circuitry pation. When activated, the thermal-shutdown circuitryThe enable inputs feature hot-swap capability. At theplaces the driver outputs into a high-impedance state. input there are two NMOS devices, M1 and M2 Receiver Input Filtering (Figure 9). When VCCramps from zero, an internal 7?sThe receivers of the MAX13080E–MAX13085E, and thetimer turns on M2 and sets the SR latch, which alsoMAX13089E when operating in 250kbps or 500kbpsturns on M1. Transistors M2, a 1.5mA current sink, andmode, incorporate input filtering in addition to inputM1, a 500?A current sink, pull DE to GND through ahysteresis. This filtering enhances noise immunity with5k?resistor. M2 is designed to pull DE to the dishttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlableddifferential signals 文档下载 免费文档下载 http://doc.wendoc.com/ that have very slow rise and fallstate against an external parasitic capacitance up totimes. Receiver propagation delay increases by 25_0pF that can drive DE high. After 7?s, the timerdue to this filtering. deactivates M2 while M1 remains on, holding DE lowagainst three-state leakages that can drive DE high. M1Fail-Safe remains on until an external source overcomes theThe MAX13080E family guarantees a logic-high receiverrequired input current. At this time, the SR latch resetsoutput when the receiver inputs are shorted or open, orand M1 turns off. When M1 turns off, DE reverts to awhen they are connected to a terminated transmissionstandard, high-impedance CMOS input. Whenever Vline with all drivers disabled. This is done by setting thedrops below 1V, the hot-swap input is reset. CCreceiver input threshold between -50mV and -200mV. IfFor REthere is a complementary circuit employing http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmltwothe differential receiver input voltage (A - B) is greaterPMOS devices pulling REto VCC. than or equal to -50mV, RO is logic-high. If (A - B) is less ________________________________________________________________________________ ______15 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E tion. Drive H/Fhigh for half-duplex operation. In full-duplex mode, the pin configuration of the driver andreceiver is the same as that of a MAX13080E. In 文档下载 免费文档下载 http://doc.wendoc.com/ half-duplex mode, the receiver inputs are internally connect-ed to the driver outputs through a resistor-divider. Thiseffectively changes the function of the device’s outputs.Y becomes the noninverting driver output and receiverinput, Z becomes the inverting driver output and receiverinput. In half-duplex mode, A and B are still connected toground through an internal resistor-divider http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlthey arenot but internally connected to the receiver. ±15kV ESD Protection As with all Maxim devices, ESD-protection structuresare incorporated on all pins to protect against electro-static discharges encountered during handling andassembly. The driver outputs and receiver inputs of theMAX13080E family of devices have extra protectionagainst static electricity. Maxim’s engineers have devel-oped state-of-the-art structures to protect these pinsagainst ESD of ±15kV without damage. The ESD struc-tures withstand high ESD in all states: normal operation,shutdown, and powered down. After an ESD event, theMAX13080E–MAX13089E keep working without latchupor damage. ESD protection can be tested in various ways. Thetransmitter outputs and receiver inputs of theMAX13080E–MAX13089E are characterized for protec-tion to the following limits: ?±15kV using the Human Body Model ?±6kV using the Contact http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlmethod 61000-4-2 ESD Test Conditions Discharge specifiedin IEC 文档下载 免费文档下载 http://doc.wendoc.com/ ESD performance depends on a variety of conditions.Contact Maxim for a reliability report that documentstest setup, test methodology, and test results. Human Body Model Figure 10a shows the Human Body Model, and Figure10b shows the current waveform it generates when dis-charged into a low impedance. This model consists of a100pF capacitor charged to the ESD voltage of interest,which is then discharged into the test device through a1.5k?resistor. IEC 61000-4-2 The IEC 61000-4-2 standard covers ESD testing andperformance of finished equipment. However, it doesnot specifically refer to integrated circuits. TheMAX13080E family of devices helps you design equip-ment to meet IEC 61000-4-2, without the need for addi-tional ESD-protection components. MAX13089E Programming The MAX13089E has several operatinghttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlmodes. programmable Transmitter rise and fall times are programma-ble, resulting in maximum data rates of 250kbps,500kbps, and 16Mbps. To select the desired data rate,drive SRL to one of three possible states by using athree-state driver: VCC, GND, or unconnected. For250kbps operation, set the three-state device in high-impedance mode or leave SRL unconnected. For500kbps operation, drive SRL high or connect it to VCC.For 16Mbps operation, drive SRL low or connect it toGND. SRL can be changed during operation withoutinterrupting data communications. 文档下载 免费文档下载 http://doc.wendoc.com/ Occasionally, twisted-pair lines are connected backwardfrom normal orientation. The MAX13089E has two pinsthat invert the phase of the driver and the receiver to cor-rect this problem. For normal operation, drive TXP andRXP low, connect them to ground, or leave them uncon-nected (internal pulldown). To invert the driver phase,drive TXP high or connect it to VCC. To invert the receiverphase, drihttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlve RXP high or connect it to VCC. Note that thereceiver threshold is positive when RXP is high. The MAX13089E can operate in full- or half-duplexmode. Drive H/Flow, leave it unconnected (internalpulldown), or connect it to GND for full-duplex opera-16 ________________________________________________________________________________ ______ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers The major difference between tests done using theHuman Body Model and IEC 61000-4-2 is higher peakcurrent in IEC 61000-4-2 because series resistance is256 Transceivers on the Bus lower in the IEC 61000-4-2 model. Hence, the ESD with-The standard RS-485 receiver input impedance is 12k?stand voltage measured to IEC 61000-4-2 is generally(1-unit load), and the standard driver can drive up to 32-lower than that measured using the Human Body Model.unit loads. The MAX13080E family of transhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlceivers has aFigure 10c shows the IEC 61000-4-2 model, and Figure1/8-unit load receiver input impedance (96k?), allowing10d shows the current waveform for IEC 61000-4-2 ESDup to 256 transceivers to be connected in parallel on oneContact Discharge test. communication line. Any combination of these devices,Machine Model 文档下载 免费文档下载 http://doc.wendoc.com/ as well as other RS-485 transceivers with a total of 32-The machine model for ESD tests all pins using aunit loads or fewer, can be connected to the line. 200pF storage capacitor and zero discharge resis-Reduced EMI and Reflections tance. The objective is to emulate the stress causedThe MAX13080E/MAX13081E/MAX13082E featurewhen I/O pins are contacted by handling equipmentreduced slew-rate drivers that minimize EMI andduring test and assembly. Of course, all pins requirereduce reflections caused by improperly terminatedthis protection, not just RS-485 inputs and outputs. cableshttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html, allowing error-free data transmission up to250kbps. The MAX13083E/MAX13084E/MAX13085Eoffer higher driver output slew-rate limits, allowingtransmit speeds up to 500kbps. The MAX13089E withSRL = VCCor unconnected are slew-rate limited. WithSRL unconnected, the MAX13089E error-free datatransmission is up to 250kbps. With SRL connected toVCC,the data transmit speeds up to 500kbps. ________________________________________________________________________________ ______ 17 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, TransceiversMAX13080E–MAX13089E Low-Power Shutdown Mode (ExceptMAX13081E/MAX13084E/MAX13087E) RS-485/RS-422 文档下载 免费文档下载 http://doc.wendoc.com/ Low-power shutdown mode is initiated by bringing bothREhigh and DE low. In shutdown, the devices typicallydraw only 2.8?A of supply current. REand DE can be driven simultaneously; the devicesare guaranteed not to enter shutdown if REis http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlhigh andDE is low for less than 50ns. If the inputs are in thisstate for at least 700ns, the devices are guaranteed toenter shutdown. Enable times tZHand tZL(see the SwitchingCharacteristics section) assume the devices were not ina low-power shutdown state. Enable times tZH(SHDN)andtZL(SHDN)assume the devices were in shutdown state. Ittakes drivers and receivers longer to become enabledfrom low-power shutdown mode (tZH(SHDN), tZL(SHDN))than from driver/receiver-disable mode (tZH, tZL). Driver Output Protection Two mechanisms prevent excessive output current andpower dissipation caused by faults or by bus contention.The first, a foldback current limit on the output stage,provides immediate protection against short circuits overthe whole common-mode voltage range (see the TypicalOperating Characteristics). The second, a thermal-shut-down circuit, forces the driver outputs into a high-imped-ance dihttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmle state temperature if the exceeds 175°C (typ). Line Length The RS-485/RS-422 standard covers line lengths up to4000ft. For line lengths greater than 4000ft, use therepeater application shown in Figure 11. 文档下载 免费文档下载 http://doc.wendoc.com/ Typical Applications The MAX13082E/MAX13085E/MAX13088E/MAX13089Etransceivers are designed for bidirectional data commu-nications on multipoint bus transmission lines. Figures12 and 13 show typical network applications circuits. To minimize reflections, terminate the line at both endsin its characteristic impedance, and keep stub lengthsoff the main line as short as possible. The slew-rate-lim-ited MAX13082E/MAX13085E and the two modes of theMAX13089E are more tolerant of imperfect termination. Chip Information TRANSISTOR COUNT: 1228PROCESS: BiCMOS Figure 11. Line Repeater for MAX13080E/MAX13081E/ MAX13083E/MAX13084E/MAX13086E/MAX13087E/MAX13089E in Full-Duplex Mode http://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.html18 ________________________________________________________________________________ ______ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers ________________________________________________________________________________ ______19 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 文档下载 免费文档下载 http://doc.wendoc.com/ MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers ________________________________________________________________________________ ______21 MAX13080E–MAX13089E 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E Ordering Information (continued) 22______________________________________________________________________________ ________ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/Rhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlS-422 Transceivers Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to .) ________________________________________________________________________________ ______23 MAX13080E–MAX13089E 文档下载 免费文档下载 http://doc.wendoc.com/ 5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to .) Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabhttp://doc.wendoc.com/b2be828f3f110692c7ce0fc0d.htmlriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________24?2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc. 文档下载网是专业的免费文档搜索与下载网站,提供行业资料,考试资料,教 学课件,学术论文,技术资料,研究报告,工作范文,资格考试,word 文档, 专业文献,应用文书,行业论文等文档搜索与文档下载,是您文档写作和查找 文档下载 免费文档下载 http://doc.wendoc.com/ 参考资料的必备网站。 文档下载 http://doc.wendoc.com/ 亿万文档资料,等你来免费下载