SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE MAY 2009 GENERAL DESCRIPTION The SP3495E - SP3497E transceivers are suitable for high speed bidirectional communication on multipoint bus transmission lines. They are designed for balanced data transmission and comply with both RS-485 and RS-422 EIA standards. Each device contains one differential driver and one differential receiver Driver differential outputs and receiver differential inputs are connected internally to form a half-duplex input/output to the RS-485 bus. Separate RE and DE pins enable and disable the driver and receiver independently or may be externally connected together as a direct control. The device enters a low power shutdown mode if both driver and receiver are disabled. the bus-pin outputs of disabled or powered down devices are in high impedance state. The high impedance driver output is maintained over the entire common-mode voltage range of -7V to +12V. SP3495E - SP3497E operates from a single 3.3V power supply. SP3495E - SP3497E transceivers load the data bus only half as much as a standard RS-485 unit load. This allows up to 64 devices to be connected simultaneously on a bus without violating required RS-485 signal margin and without using repeaters. Excessive power dissipation caused by bus contention or by shorting outputs to ground or a voltage source is prevented by short circuit protection and thermal shutdown. This feature forces the driver output into high impedance state if the absolute value of the output current exceeds 250mA or if junction temperature exceeds 165°C. Receivers will fail-safe to a logic high output state if the inputs are unconnected (floating) or shorted. All RS-485 inputs REV. 1.0.0 and outputs are ESD protected up to +/-15kV Human Body Model. FEATURES • 3.3V Single Supply Operation • High Speed up to 32Mbps • Robust +/-15kV ESD protection • Hot Swap glitch protection • Advanced Fail-safe Receiver Inputs • Half Unit Load, 64 Transceivers on bus • Driver short circuit current limit and thermal shutdown for overload protection • Low Current 1uA shutdown mode TYPICAL APPLICATIONS • Factory Automation Controls • Motor Control • Industrial Process Control • Building Automation • Security Systems • Remote Utility Meter Reading • Long or un-terminated transmission lines FIGURE 1. TYPICAL APPLICATION CIRCUIT Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 FIGURE 2. PIN OUT ASSIGNMENT SP3495E 8-Pin Half Duplex RO 1 R 2 RE DE 3 4 DI 8 VCC 7 B 6 A D 5 GND SP3496E 8-pin Full Duplex Vcc R D GND 1 2 R 8 A 7 B 6 3 D 4 Z 5 Y SP3497E 14-pin Full Duplex NC R 1 2 R RE 3 4 DE 14 13 12 11 10 D 5 6 GND 7 GND D 9 8 Vcc NC A B Z Y NC ORDERING INFORMATION PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS SP3495EEN-L 8-pin Narrow SOIC -40°C to +85°C Active SP3495EEN-L/TR 8-pin Narrow SOIC -40°C to +85°C Active SP3496EEN-L 8-pin Narrow SOIC -40°C to +85°C Active SP3496EEN-L/TR 8-pin Narrow SOIC -40°C to +85°C Active SP3497EEN-L 14-pin Narrow SOIC -40°C to +85°C Active SP3497EEN-L/TR 14-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 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE PIN DESCRIPTIONS Pin Assignments PIN NUMBER HALF DUPLEX FULL DUPLEX SP3495E SP3496E SP3497E 1 2 2 2 3 - - 3 4 PIN NAME TYPE DESCRIPTION RO O Receiver Output. When RE is low and if (AB) ≥ -40mV, 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 +3.3V power supply input. Bypass with 0.1uF capacitor. - 8 12 A I Non-Inverting Receiver Input - 7 11 B I Inverting Reciever 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 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE 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 +6.0V Input Voltage at control pins (RE, DE and DI) -0.5V to (VCC + 0.3V) Voltage Range on A and B pins -9V to +14V Storage Temperature Range -65°C to + 150°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 = +3.0V TO +3.6V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +3.3V AND 25OC. SYMBOL PARAMETERS MIN. TYP. MAX. UNITS Vcc V CONDITIONS DRIVER DC CHARACTERISTICS VOD ∆VOD Differential Driver Output Change in Magnitude of Differential Output No Load 2.0 RL = 100Ω (RS-422), Figure 3 1.5 RL = 54Ω (RS-485), Figure 3 1.5 VCM = -7V, Figure 4 1.5 VCM = +12V, Figure 4 -0.20 0.20 V RL = 100Ω (RS-422), Figure 3, See note 1 -0.20 0.20 RL = 54Ω (RS-485), Figure 3, See note 1 -0.20 0.20 VCM = -7V, Figure 4, See note 1 VCM = +12V, Figure 4, See note 1 -0.20 0.20 Driver Common Mode Output Voltage steady state 1.3 2.5 V Figure 3 ∆VOC Change in Magnitude of Common Mode Output Voltage -0.2 0.2 V Figure 3, See note 1 IDSC Driver Short Circuit Current Limit -250 VOC 250 4 mA VOUT Forced to -7V, Figure 5 mA VOUT Forced to +12V, Figure 5 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE UNLESS OTHERWISE NOTED: VCC = +3.0V TO +3.6V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +3.3V AND 25OC. SYMBOL VIH PARAMETERS MIN. TYP. 2.0 IIN UNITS CONDITIONS V Logic Input High V Logic Input Low Logic Input Thresholds (DI, DE, RE) VIL VHYS MAX. 0.8 Driver Input Hysteresis 100 Logic Input Current (DI, DE and RE) 10 -10 mV TA = 25°C uA IN = 0V uA IN = Vcc Driver AC Characteristics freq Data Signaling Rate 32 tPLH Driver Propagation Delay (low to High) 5 Driver Propagation Delay (High to Low) 5 tPHL tR Driver Rise Time Mbps 1/tUI, Duty Cycle 40 to 60% 11 24 ns CL = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 11 24 ns CL = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 2.5 4.5 10 ns CL = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 tF Driver Fall time 2.5 4.5 10 ns CL = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 |tPLH-tPHL| Differential Pulse Skew 3 ns Figures 6 and 7 tOZH Driver Enable to Output High 50 ns CL = 50pF, RL = 500Ω, Figures 8 and 9 tOZL Driver Enable to Outut Low 50 ns CL = 50pF, RL = 500Ω, Figures 10 and 11 tOHZ Driver Disable from Output High 50 ns CL = 50pF, RL = 500Ω, Figures 8 and 9 tOLZ Driver Disable from Output Low 50 ns CL = 50pF, RL = 500Ω, Figures 10 and 11 tOZV Shutdown to Driver Output Valid 6 us CL = 50pF, RL = 500Ω 50 600 ns Note 2 and 3 -290 500 uA DE = 0, Vcc = 0 or 3.3V VA or VB = 12V, other input 0V tSHDN Time to Shutdown RECEIVER DC CHARACTERISTICS IIN Input Current (A, B pins) VA or VB = -7V, other input 0V VIH VIL Receiver Differential Thresholds (VA - VB) -200 Receiver Input Hysteresis VOH Receiver Output Voltage High VOL Receiver Output Voltage Low mV -7V ≤ VCM ≤ 12V, rising -125 mV -7V ≤ VCM ≤ 12V, falling 25 mV VCM = 0V -85 -40 2.4 0.4 5 V IOUT = -8mA, VID = 200mV V IOUT = 8mA, VID = -200mV SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE UNLESS OTHERWISE NOTED: VCC = +3.0V TO +3.6V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +3.3V AND 25OC. SYMBOL IOZ PARAMETERS High-Z Receiver Output Current MIN. TYP. MAX. -1 1 IOSS RIN Receiver Output Short Circuit Current -95 Receiver Input Resistance 24 95 UNITS CONDITIONS uA RE = Vcc, VOUT = 0V uA RE = Vcc, VOUT = Vcc mA VOUT = 0V mA VOUT = Vcc KΩ -7V ≤ VCM ≤ 12V RECEIVER AC CHARACTERISTICS freq Data Signaling Rate 32 Mbps 1/tUI, Duty Cycle 40 to 60% tPLH Receiver Propagation Delay (Low to High) 15 40 ns VID = +/-2V, CL = 15pF, Freq = 8MHz, Figure 12 and 13 tPHL Receiver Propagation Delay (High to Low) 15 40 ns VID = +/-2V, CL = 15pF, Freq = 8MHz, Figure 12 and 13 skew Receiver Propagation Delay Skew 3 ns VID = +/-2V, CL = 15pF, Freq = 8MHz, Figure 12 and 13 skew = |tPLH-tPHL| tR Receiver Output Rise Time 1 2 6 ns CL = 15pF, Freq = 8MHz tF Receiver Output Fall Time 1 2 6 ns CL = 15pF, Freq = 8MHz tZH Receiver Enable to Output High 50 ns CL = 15pF, RL = 1kΩ, Figure 14 tZL Receiver Enable to Output Low 50 ns CL = 15pF, RL = 1kΩ, Figure 14 tHZ Receiver Output High to Disable 50 ns CL = 15pF, RL = 1kΩ, Figure 14 tLZ Receiver Output Low to Disable 50 ns CL = 15pF, RL = 1kΩ, Figure 14 tZH(SHDN) Shutdown to Receiver Output Valid High 6 us CL = 15pF, RL = 1kΩ tZL(SHDN) Shutdown to Receiver Output Valid Low 6 us CL = 15pF, RL = 1kΩ 600 ns Note 2 and 3 tSHDN Time to Shutdown 50 POWER REQUIRMENTS AND RECOMMENDED OPERATING CONDITIONS Vcc Supply Voltage ICC1 3.0 3.3 3.6 V Supply Current - Driver Enabled 5.0 mA DE = Vcc, No Load, RE and DI = 0V or Vcc ICC2 Supply Current - Receiver Enabled 5.0 mA DE = 0V, RE = 0V, No Load ICC3 Supply Current - Shutdown Mode 1 6 uA DE = 0V, RE = Vcc, DI = Vcc or 0V TSD Thermal Shutdown Temperature 165 6 °C SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE UNLESS OTHERWISE NOTED: VCC = +3.0V TO +3.6V WITH TA FROM -40OC TO +85OC. TYPICAL VALUES ARE AT VCC = +3.3V AND 25OC. SYMBOL PARAMETERS MIN. Thermal Shutdown Hysteresis ESD Protection at Pins A, B, Y and Z TYP. MAX. UNITS 20 °C +/-15 kV CONDITIONS Human Body Model 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. Gauranteed by design and bench characterization. 7 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE FIGURE 3. DRIVER DC TEST CIRCUIT R/2 DI VOD D R/2 VCC VOC FIGURE 4. DRIVER COMMON MODE LOAD TEST DE = 3.3V 375Ω A/Y DI = 0 or Vcc D 60Ω VOD B/Z 375Ω FIGURE 5. DRIVER SHORT CIRCUIT CURRENT LIMIT TEST DE = 0 or Vcc DI = 0 or Vcc A/Y IOSD D B/Z 100Ω -7V to +12V V 8 VCM SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE 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 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE FIGURE 9. DRIVER ENABLE DISABLE TIMING DIAGRAM 1 Vcc DE Vcc/2 0 tZH, tZH(SHDN) OUT 0.25V VOM = (VOL + Vcc)/2 t HZ 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 0 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE FIGURE 11. DRIVER ENABLE AND DISABLE TIMING DIAGRAM 2 Vcc Vcc/2 DE 0 tZL, tZL(SHDN) t LZ Vcc OUT VOL VOM = (VOL + Vcc)/2 0.25V FIGURE 12. RECEIVER PROPAGATION DELAY TEST CIRCUIT A VID B R RE OUT CL 15pF FIGURE 13. RECEIVER PROPAGATION DELAY TIMING DIAGRAM +1V A B t PHL t PLH -1V VOH 1.5V VOL OUT 11 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE FIGURE 14. RECEIVER ENABLE AND DISABLE TIMES TEST CIRCUIT 1.5V S1 S3 B -1.5V R A S2 RE GENERATOR Vcc 1kΩ CL= 15pF 50Ω 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 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE 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 13 SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 1.0 PRODUCT DESCRIPTION The SP349xE high speed transceivers contain one driver and one receiver. The SP3495 is a half-duplex design while the SP3496E and SP3497E are full-duplex designs. The control pins RE and DE feature a hotswap capability allowing live insertion without spurious data transfer. 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 The Receivers incorporate fail-safe circuitry, which 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 SP349xE interprets 0V differential as a logic high with a minimum 40mV noise margin. HOT-SWAP CAPABILITY When Vcc is first applied the SP349xE holds the driver enable and receiver enable inactive for approximately 10 microseconds. During power ramp-up other system IC’s may drive unpredictable values. Hot-swap capability prevents the SP349xE from driving any output signal until power has stabilized. After the initial power-up sequence, the hot-swap circuit becomes transparent and driver enable and receiver enable resume their normal functions and timings 14 SP3495E-3497E REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE PACKAGE DIMENSIONS (14 PIN NSOIC) 15 SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE PACKAGE DIMENSIONS (8 PIN NSOIC) 16 REV. 1.0.0 SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 REVISION HISTORY DATE REVISION 5/01/09 1.0.0 DESCRIPTION Production Release. 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 2009 EXAR Corporation Datasheet May 2009. Send your technical inquiries with details to our e-mail hotline: [email protected]. Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. 17