XR5487EIDTR-F

XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION AUGUST 2011 REV. 1.0.2 GENERAL DESCRIPTION FEATURES The XR5486E-XR5488E family of RS-485 devices are designed for reliable, bidirectional communication on multipoint bus transmission lines. Each device contains one differential driver and one differential receiver. XR5488E is a half-duplex device while the other part numbers are full-duplex. All devices comply with TIA/EIA-485 and TIA/EIA-422 standards. Leadfree and RoHS compliant packages are available for all models. These devices are ruggedized for use in harsh operating conditions over the entire common mode voltage range from -7V to +12V. Receivers are specially designed to fail-safe to a logic high output state if the inputs are left un-driven or shorted. All RS485 bus-pins are protected against severe ESD events up to +/-15kV Air-Gap (IEC-61000-4-2), up to +/-8kV Contact Discharge (IEC-61000-4-2) and up to +/-15kV Human body Model. Drivers are protected from excess current flow caused by bus contention or output short-circuits by both an internal current limit and a thermal-overload shutdown. Devices are rated for Industrial (-40°C to +85°C) operating temperatures. Receivers have exceptionally high input impedance, which places only 1/8th the standard load on a bus. Up to 256 transceivers may coexist while preserving full signal margin. All devices operate from a single 5.0V power supply and draw negligible quiescent power. All versions except the XR5487E may independently enable and disable their driver and receiver and enter a low power shutdown mode if both driver and receiver are disabled. All outputs maintain high impedance in shutdown or when powered-off. • 5.0V Single Supply Operation • High Speed up to 52Mbps • Advanced Fail-safe Receiver Inputs • Hot Swap glitch protection on control inputs • Robust ESD Protection for RS-485 pins ■ +/-15kV Air-Gap Discharge ■ +/-15kV Human Body Model ■ +/-8kV Contact Discharge • 1/8th Unit Load, 256 transceivers on bus • Driver short circuit current limit and thermal shutdown for overload protection • Low Current 1μA shutdown mode (except XR5487E) • Industry standard package footprints TYPICAL APPLICATIONS • Motor Control • Building Automation • Security Systems • Remote Utility Meter Reading FIGURE 1. TYPICAL APPLICATION CIRCUIT DE DE XR5488E DI XR5488E B B STUB RT DI RT A A RO RO B RE A XR5488E A XR5488E B DE RE RE DE DI RO RE DI RO Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 FIGURE 2. PIN OUT ASSIGNMENT 8 VCC RO 1 RE 2 DE 3 DI 4 5 GND VCC 1 8 A RO 2 7 B DI 3 6 Z GND 4 5 Y NC 1 14 VCC RO 2 13 NC RE 3 DE 4 DI 5 GND 6 9 GND 7 8 NC 8-Pin NSOIC Half Duplex XR5488E 8-Pin NSOIC Full Duplex XR5487E 14-Pin NSOIC Full Duplex XR5486E 7 B 6 A 12 A 11 B 10 Z Y ORDERING INFORMATION PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS XR5486EID-F 14-pin Narrow SOIC -40°C to +85°C Active XR5487EID-F 8-pin Narrow SOIC -40°C to +85°C Active XR5488EID-F 8-pin Narrow SOIC -40°C to +85°C Active Note: To order Tape and Reel option include "/TR" in ordering part number. All packages are Pb-free/ RoHS compliant. 2 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION PIN DESCRIPTIONS Pin Assignments PIN NUMBER HALF DUPLEX FULL DUPLEX XR5488E XR5487E XR5486E 1 2 2 2 3 - - 3 4 PIN NAME TYPE DESCRIPTION RO O Receiver Output. When RE is low and if (AB) ≥ -50mV, RO is High. If (A-B) ≤ -200mV, RO is Low. I Receiver Output Enable. When RE is Low, RO is enabled. When RE is High, RO is high impedance. RE should be High and DE should be low to enter shutdown mode. RE is a hot-swap input. I Driver Output Enable. When DE is High, outputs are enabled. When DE is low, outputs are high impedance. DE should be low and RE should be High to enter shutdown mode. DE is a hot-swap input. Driver Input. With DE high, a low level on DI forces Non-Inverting output low and inverting output high. Similarly, a high level on DI forces Non-Inverting output High and Inverting output Low. RE DE 4 3 5 DI I 5 4 6, 7 GND Pwr 6 - - A O Non-Inverting Receiver Input and NonInverting Driver Output. 7 - - B O Inverting Receiver Input and Inverting Driver Output. 8 1 14 Vcc Pwr +5.0V power supply input. Bypass with 0.1uF capacitor. - 8 12 A I Non-Inverting Receiver Input. - 7 11 B I Inverting Receiver Input. - 5 9 Y O Non-Inverting Driver Output. - 6 10 Z O Inverting Driver Output. - - 1, 8, 13 NC - No Connect, not internally connected. Pin type: I=Input, O=Output. 3 Ground. XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 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 to the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability and cause permanent damage to the device. Vcc ≤ +7.0V VCC Input voltage at control pins (RE, DE) -0.3V to (VCC + 0.3V) Driver input voltage (DI) -0.3V to (VCC + 0.3V) Receiver output voltage (RO) -0.3V to (VCC + 0.3V) Driver output voltage (A, B, Y and Z) -8V to +13V Receiver input voltage (A, B) -8V to +13V Voltage input range, transient pulse, A, B, Y and Z, through 100Ω, see Figure 19. +/-65.0V Storage temperature range -65°C to + 150°C Lead temperature +300°C Power Dissipation Maximum Junction Temperature 150°C 8-Pin SO θJA = 128.4°C/W 14-Pin SO θJA = 86°C/W CAUTION: ESD (Electrostatic Discharge) sensitive device. Permanent damage may occur on unconnected devices subject to high energy electrostatic fields. Unused devices must be stored in conductive foam or shunts. Personnel should be properly grounded prior to handling this device. The protective foam should be discharged to the destination socket before devices are removed. ELECTRICAL CHARACTERISTICS UNLESS OTHERWISE NOTED: VCC = +5.0V +/-0.25V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +5.0V AND 25OC. SYMBOL PARAMETERS MIN TYP MAX UNITS CONDITIONS DRIVER DC CHARACTERISTICS Vcc No Load 2.8 VOD ΔVOD Differential Driver Output Change in Magnitude of Differential Output RL = 100Ω (RS-422), Figure 3 2.4 V RL = 54Ω (RS-485), Figure 3 2.4 VCM = -7V, Figure 4 2.4 VCM = +12V, Figure 4 -0.20 0.20 RL = 100Ω (RS-422), Figure 3, See note 1 -0.20 0.20 RL = 54Ω (RS-485), Figure 3, See note 1 V -0.20 0.20 -0.20 0.20 4 VCM = -7V, Figure 4, See note 1 VCM = +12V, Figure 4, See note 1 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION UNLESS OTHERWISE NOTED: VCC = +5.0V +/-0.25V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +5.0V AND 25OC. SYMBOL VOC PARAMETERS MIN TYP Driver Common Mode Output Voltage steady state MAX UNITS CONDITIONS 3.0 V Figure 3 Figure 3, See note 1 ΔVOC Change in Magnitude of Common Mode Output Voltage -0.2 0.2 V IOSD Driver Short Circuit Current Limit -250 250 mA -7V ≤ VOUT ≤ +12V, Figure 5 Output Leakage Current (FullDuplex versions, Y and Z pins) -75 125 μA DE = 0V, RE = 0V, Vcc = 0V or 5V, -7V ≤ VOUT ≤ +12V V Logic Input High V Logic Input Low IOL VIH VIL VHYS IIN Logic Input Thresholds (DI, DE, RE) 2.0 0.8 Driver Input Hysteresis Logic Input Current (DI, DE and RE) 100 -1 1 mV TA = 25°C μA 0V ≤ IN ≤ +VCC, after first transition Mbps 1/tUI, Duty Cycle 40 to 60%, Figure 4, CL = 50pF, RL = 54Ω. DRIVER AC CHARACTERISTICS freq Data Signaling Rate 52 tPLH Driver Propagation Delay (Low to High) 4 25 ns tPHL Driver Propagation Delay (High to Low) 4 25 ns CL = 50pF, RL = 54Ω, Figures 6 and 7 CL = 50pF, RL = 54Ω, Figures 6 and 7 CL = 50pF, RL = 54Ω, tR Driver Rise Time 2 8 ns tF Driver Fall time 2 8 ns +/-3 ns Figures 6 and 7 |tPLH-tPHL| Differential Pulse Skew Figures 6 and 7 CL = 50pF, RL = 54Ω, Figures 6 and 7 tZH Driver Enable to Output High 60 ns CL = 50pF, RL = 500Ω, Figures 8 and 9 tZL Driver Enable to Output Low 60 ns CL = 50pF, RL = 500Ω, Figures 10 and 11 tHZ Driver Disable from Output High 60 ns CL = 50pF, RL = 500Ω, Figures 8 and 9 tLZ Driver Disable from Output Low 60 ns CL = 50pF, RL = 500Ω, Figures 10 and 11 tZV Shutdown to Driver Output Valid 1 μs CL = 50pF, RL = 500Ω 600 ns Notes 2, 3 and 4 tSHDN Time to Shutdown 50 200 5 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 UNLESS OTHERWISE NOTED: VCC = +5.0V +/-0.25V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +5.0V AND 25OC. SYMBOL PARAMETERS MIN TYP MAX UNITS 125 μA CONDITIONS RECEIVER DC CHARACTERISTICS IIN Input Current (A, B pins) -75 DE = 0, Vcc = 0 or 3.3V VA or VB = 12V, other input 0V VA or VB = -7V, other input 0V VIH VIL Receiver Differential Thresholds (VA - VB) -50 -200 Receiver Input Hysteresis VOH Receiver Output Voltage High VOL Receiver Output Voltage Low IOZ High-Z Receiver Output Current IOSS Receiver Output Short Circuit Current RIN Receiver Input Resistance 25 Vcc 1.2 mV -7V ≤ VCM ≤ +12V, rising mV -7V ≤ VCM ≤ +12V, falling mV VCM = 0V V IOUT = -8mA, VID = -50mV 0.4 V IOUT = 8mA, VID = -200mV +/-1 μA RE = Vcc, 0.40 ≤ VOUT ≤ +/-125 mA 0 ≤ VRO ≤ Vcc 96 KΩ -7V ≤ VCM ≤ 52 Mbps +2.4V +12V RECEIVER AC CHARACTERISTICS 1/tUI, Duty Cycle 40 to 60%, freq Data Signaling Rate tPLH Receiver Propagation Delay (Low to High) 20 30 ns VID = +/-2V, CL = 15pF, Figures 12 and 13 tPHL Receiver Propagation Delay (High to Low) 20 30 ns VID = +/-2V, CL = 15pF, Figures 12 and 13 skew Receiver Propagation Delay Skew CL = 15pF +/-3 ns VID = +/-2V, CL = 15pF, Figures 12 and 13 skew = |tPLH-tPHL| tR Receiver Output Rise Time 2 4 ns CL = 15pF tF Receiver Output Fall Time 2 4 ns CL = 15pF tZH Receiver Enable to Output High 40 ns tZL Receiver Enable to Output Low 40 ns tHZ Receiver Disable from Output High 40 ns tLZ Receiver Disable from Output Low 40 ns tZH(SHDN) Shutdown to Receiver Output Valid High 1 μs 6 CL = 15pF, RL = 1kΩ, Figures 14 and 15 CL = 15pF, RL = 1kΩ, Figures 14 and 16 CL = 15pF, RL = 1kΩ, Figures 14 and 17 CL = 15pF, RL = 1kΩ, Figures 14 and 18 CL = 15pF, RL = 1kΩ, Figures 14 and 15 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION UNLESS OTHERWISE NOTED: VCC = +5.0V +/-0.25V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +5.0V AND 25OC. SYMBOL PARAMETERS tZL(SHDN) Shutdown to Receiver Output Valid Low tSHDN Time to Shutdown MIN TYP 50 200 MAX UNITS CONDITIONS 1 μs CL = 15pF, RL = 1kΩ, Figures 14 and 16 600 ns Notes 2, 3 and 4 POWER REQUIREMENTS AND RECOMMENDED OPERATING CONDITIONS Vcc Supply Voltage 4.75 ICC1 Supply Current - Active Mode ICC2 Supply Current - Shutdown Mode TSD Thermal Shutdown Temperature 165 °C Thermal Shutdown Hysteresis 20 °C +/-15 kV Human Body Model +/-15 kV IEC-61000-4-2 Air Discharge +/-8 kV IEC-61000-4-2 Contact Discharge +/-2 kV Human Body Model +/-200 V Machine Model ESD Protection at Pins A, B, Y and Z pins ESD Protection for RO, DI, DE and RE pins 5.0 5.25 V 800 1500 μA No Load, DE = RE = Vcc or 0V, DI = 0V or Vcc 1 μA DE = 0V, RE = Vcc, DI = Vcc or 0V NOTE: 1. Change in Magnitude of Differential Output Voltage and Change in Magnitude of Common Mode Output Voltage are the changes in output voltage when DI input changes state. 2. The transceivers are put into shutdown by bringing RE High and DE Low simultaneously for at least 600ns. If the control inputs are in this state for less than 50ns, the device is guaranteed not enter shutdown. If the enable inputs are held in this state for at least 600ns the device is assured to be in shutdown. Note that the receiver and driver enable times increase during shutdown. 3. Guaranteed by design and bench characterization. 4. Except devices which do not have DE or RE inputs. 7 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 3. DRIVER DC TEST CIRCUIT FIGURE 4. DRIVER COMMON MODE LOAD TEST V DE Vcc/2 tZH, tZH(SHDN) OUT 0.25 VOM = (VOL + Vcc)/2 t HZ FIGURE 5. DRIVER SHORT CIRCUIT CURRENT LIMIT TEST 8 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 6. DRIVER PROPAGATION DELAY TEST CIRCUIT RL 54Ω Y DI D CL 50pF VOD Z 3.3V FIGURE 7. DRIVER PROPAGATION DELAY TIMING DIAGRAM Vcc DI Vcc/2 Vcc/2 0V Z t PLH t PHL VO 1/2VO 1/2VO Y VDIFF VY – VZ t DPLH VO+ 0V VO– t DPHL 90% 10% tF 90% 10% tR t SKEW = |t DPLH - t DPHL| FIGURE 8. DRIVER ENABLE AND DISABLE TIME TEST CIRCUIT 1 Y 0 or Vcc DI D OUT Z GENERATOR S1 CL = 50pF 50Ω 9 RL = 500Ω XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 9. DRIVER ENABLE DISABLE TIMING DIAGRAM 1 FIGURE 10. DRIVER ENABLE AND DISABLE TIME TEST CIRCUIT 2 Vcc RL = 500Ω Y 0 or Vcc DI OUT Z GENERATOR S1 D CL = 50pF 50Ω 10 REV. 1.0.2 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 11. DRIVER ENABLE AND DISABLE TIMING DIAGRAM 2 FIGURE 12. RECEIVER PROPAGATION DELAY TEST CIRCUIT FIGURE 13. RECEIVER PROPAGATION DELAY TIMING DIAGRAM +1V A B t PHL t PLH -1V VOH 1.5V VOL OUT 11 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 14. RECEIVER ENABLE AND DISABLE TIMES TEST CIRCUIT FIGURE 15. RECEIVER ENABLE AND DISABLE TIMING DIAGRAM 1 S1 is open, S2 is closed, S3 = 1.5V 3V 1.5V RE t ZH, t ZH(SHDN) VOH OUT VOH /2 0V FIGURE 16. RECEIVER ENABLE AND DISABLE TIMING DIAGRAM 2 S1 is closed, S2 is open, S3 = -1.5V 3V 1.5V RE t ZL,t ZL(SHDN) 0V VCC OUT VOL= VCC /2 VOL 12 REV. 1.0.2 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION FIGURE 17. RECEIVER ENABLE AND DISABLE TIMING DIAGRAM 3 S1 is open, S2 is closed, S3 = 1.5V 3V RE 1.5V tHZ 0.25V VOH 0V OUT FIGURE 18. RECEIVER ENABLE AND DISABLE TIMING DIAGRAM 4 S1 is closed, S2 is open, S3 = -1.5V 3V RE 1.5V 0V t LZ VCC OUT 0.25V VOL FIGURE 19. TRANSIENT OVER VOLTAGE TOLERANCE TEST CIRCUIT 1 13 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 1.0 PRODUCT DESCRIPTION XR5486E-XR5488E is a family of advanced RS-485/RS-422 transceivers. Each contain one driver and one receiver. The XR5488E is a half-duplex design while the XR5486E and XR5487E are full-duplex designs. All devices operate from a single 5.0V power supply. These devices feature failsafe circuitry that guarantees a logic-high receiver output when the inputs are open or shorted, or when they are connected to a terminated transmission line with all drivers disabled. The control pins RE and DE feature a hotswap capability allowing live insertion without spurious data transfer. The drivers are not slew rate limited making transmit speeds up to 52Mbps possible. Drivers are output short-circuit current limited. Thermal-shutdown circuitry protects drivers against excessive power dissipation. When activited, the thermal-shutdown circuitry forces the driver outptus into a high-impedance state. ADVANCED FAILSAFE Ordinary RS-485 differential receivers will be in an indeterminate state whenever the data bus is not being actively driven. The Advanced Failsafe feature of the XR5486E-XR5488E family guarantees a logic-high receiver output when the receiver inputs are open or shorted, or when they are connected to a terminated transmission line with all drivers disabled. In a terminated bus with all transmitters disabled, the receivers’ differential input voltage is pulled to 0V by the termination. The XR5486E-XR5488E family interprets 0V differential as a logic high with a minimum 50mV noise margin while maintaining compliance with the EIA/TIA485 standard of +/-200mV. HOT-SWAP CAPABILITY When a micro-processor or other logic device undergoes its power-up sequence, its logic-outputs are typically at high impedance. In this state they are unable to drive the DE and RE signals to a defined logic level. During this period, noise, parasitic coupling or leakage from other devices could cause standard CMOS enable inputs to drift to an incorrect logic level. If circuit boards are inserted into an energized backplane (commonly called "live insertion" or "hot-swap") power may suddenly be applied to all circuits. Without the hot-swap capability, this situation could improperly enable the transceiver’s driver or receiver, driving invalid data onto shared busses and possibly causing driver contention or device damage. The XR5486E-XR5488E family contains a special power-on-reset circuit that holds the driver enable and receiver enable inactive for approximately 10 microseconds. After this initial power-up sequence the hot-swap circuit becomes transparent and driver enable and receiver enable resume their normal un-skewed functions and timings. +/-15kV ESD PROTECTION ESD protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. The driver outputs and receiver inputs of the XR5486E-XR5488E family have extra protection against static electricity. Exar uses state of the art structures to protect these pins against ESD of +/-15kV without damage. The ESD structures withstand high ESD in all states: normal operation, shutdown and powered down. After an ESD event, the XR5486E-XR5488E family keep operating without latch-up or damage. ESD protection can be tested in various ways. The transmitter outputs and receiver inputs of the XR5486EXR5488E family are characterized for protection to the following limits: ■ +/-15kV using the Human Body Model ■ +/-8kV using the Contact Discharge Model ■ +/-15kV using the Airgap Discharge Model ESD TEST CONDITIONS ESD performance depends on a variety of conditions. Contact Exar for a reliability report that documents test setup, methodology and results. 14 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION IEC 61000-4-2 The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. However, it does not specifically refer to integrated circuits. The XR5486E-XR5488E family helps you design equipment to meet IEC 61000-4-2, without sacrificing board-space and cost for external ESD-protection components. The major differences between tests done using the Human body model and IEC 61000-4-2 is a higher peak current in IEC 61000-4-2. Series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD withstand voltage measured to IEC 61000-4-2 is generally lower than that of human body model. The air-gap test involves approaching the device with a charged probe. The contact discharge method connects the probe to the device before the probe is energized. MACHINE MODEL The machine model for ESD tests all pins using a 200pF storage capacitor and zero discharge resistance. The objective is to emulate the stress caused when I/O pins are contacted by handling equipment during test and assembly. 256 TRANSCEIVERS ON THE BUS The standard RS-485 receiver input impedance is 12k Ohms (1 unit load). A standard driver can drive up to 32 unit loads. The XR5486E-XR5488E family of transceivers have only a 1/8th unit load receiver input impedance of 96k Ohms, thereby allowing eight times as many, up to 256, transceivers to be connected in parallel on a communication line. Any combination of these devices and other RS-485 transceivers up to a total of 32 unit loads may be connected to the line. LOW POWER SHUTDOWN MODE Low-power shutdown mode is initiated by bringing both RE high and DE low simultaneously. While in shutdown devices draw only 50nA of supply current. DE and RE may be tied together and driven by a single control signal. Devices 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 shutdown. Enable times tZH and tZL apply when the part is not in low-power shutdown state. Enable times tZH(SHDN) and tZL(SHDN) apply when the parts are shutdown. The drivers and receivers take longer to become enabled from low-power shutdown tZH(SHDN) and tZL(SHDN) than from driver / receiver disable mode (tZH and tZL). DRIVER OUTPUT PROTECTION Two mechanisms prevent excessive output current and power dissipation caused by faults or by bus contention. First, a driver current limit on the output stage provides immediate protection against short circuits over the whole common-mode voltage range. Second, a thermal-shutdown circuit forces the driver outputs into a high-impedance state if junction temperature becomes excessive. LINE LENGTH The RS-485/RS-422 standard covers line lengths up to 4000ft. Maximum achievable line length is a function of signal attenuation and noise. Termination prevents signal reflections by eliminating the impedance mismatches on a transmission line. Line termination is generaly used if rise and fall times are shorter than the round-trip signal propagation time. 15 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION 2.0 FUNCTION TABLES TABLE 1: FULL DUPLEX 14 PIN XR5486E TRANSMITTING Inputs Outputs RE DE DI Y Z X 1 1 1 0 X 1 0 0 1 0 0 X High-Z 1 0 X Shutdown TABLE 2: FULL DUPLEX 8 PIN XR5487E TRANSMITTING Input Outputs DI Y Z 1 1 0 0 0 1 TABLE 3: HALF DUPLEX XR5488E TRANSMITTING Inputs Outputs RE DE DI A B X 1 1 1 0 X 1 0 0 1 0 0 X High-Z 1 0 X Shutdown 16 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION TABLE 4: FULL DUPLEX 14 PIN XR5486E RECEIVING Inputs Ouptut RE DE VA - VB RO 0 X ≥ -50mV 1 0 X ≤ -200mV 0 0 X Open/Shorted 1 1 1 X High-Z 1 0 X Shutdown TABLE 5: FULL DUPLEX 8 PIN XR5487E RECEIVING Inputs Output VA - VB RO ≥ -50mV 1 ≤ -200mV 0 Open/Shorted 1 TABLE 6: HALF DUPLEX XR5488E RECEIVING Inputs Output RE DE VA - VB RO 0 X ≥ -50mV 1 0 X ≤ -200mV 0 0 X Open/Shorted 1 1 1 X High-Z 1 0 X Shutdown Note: Receiver inputs -200mV < VA - VB < -50mV should be considered indeterminate. 17 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 3.0 PRODUCT SELECTOR GUIDE TABLE 7: SELECTION GUIDE RECEIVER SHUTDOWN AND DRIVER ENABLE PART NUMBER DUPLEX DATA RATE MBPS XR5486E Full 52 Yes XR5487E Full 52 XR5488E Half 52 TRANS ON BUS FOOT-PRINT Yes 256 SN75180 No No 256 SN75179 Yes Yes 256 SN75176 4.0 TYPICAL APPLICATIONS: H alf-D uplex N etw ork RT STUB RT Bi-Directional Full-Duplex Network 18 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION Point to Multi-point with Repeater Repeater (optional) 19 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION PACKAGE DIMENSIONS (14 PIN NSOIC) 20 REV. 1.0.2 XR5486E-5488E REV. 1.0.2 ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION PACKAGE DIMENSIONS (8 PIN NSOIC) 21 XR5486E-5488E ULTRA HIGH SPEED RS-485/RS-422 PROFIBUS TRANSCEIVERS WITH 1/8TH UNIT LOAD AND +/-15KV ESD-PROTECTION REV. 1.0.2 REVISION HISTORY DATE REVISION DESCRIPTION November 2009 Rev 1.0.0 October 2010 1.0.1 Add PROFIBUS logo to front page August 2011 1.0.2 Change driver rise and fall time from 2ns minimum to 2ns typical. Add +/-65V Transient over voltage tolerance to ABS Max Ratings and add Figure 19 Transient test circuit. Released datasheet. NOTICE EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a user’s specific application. While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances. Copyright 2011 EXAR Corporation Datasheet August 2011. Send your serial transceiver technical inquiries with details to our e-mail hotline: serialtechsupport@exar.com. Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. 22