SP3495E EXAR | Alldatasheet

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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 MAY 2009 REV. 1.0.0 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 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 cu rrent 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

HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 Note: To order Tape and Reel option include "/TR" in ordering part number. All packages are Pb-free/ RoHS compliant. FIGURE 2. PIN OUT ASSIGNMENT

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 D R A B RO GND DE VCC RE DI SP3495E 8-Pin Half Duplex D R A B Z Y R GND 4 5 D Vcc SP3496E 8-pin Full Duplex Vcc D R NC A B Z Y R NC NC DE RE GND GND 7 8 D SP3497E 14-pin Full Duplex

REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE PIN DESCRIPTIONS Pin type: I=Input, O=Output. Pin Assignments PIN NUMBER PIN NAME TYPE DESCRIPTION HALF DUPLEX FULL DUPLEX SP3495E SP3496E SP3497E

122 R O O

Receiver Output. When RE is low and if (A- B) ≥ -40mV, RO is High. If (A-B) ≤ -200mV, RO is Low. 2-3 R E 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. 3-4 D E I Driver Output Enable. When DE is High, outputs are enabled. When DE is low, out- puts are high impedance. DE should be low and RE should be High to enter shutdown mode. DE is a hot-swap input

435 D I I

Driver Input. With DE high, a low level on DI forces Non-Inverting output low and invert- ing output high. Similarly, a high level on DI forces Non-Inverting output High and Invert- ing output Low. 54 6 , 7 G N D P w r G r o u n d 6-- A O Non-Inverting Receiver Input and Non- Inverting Driver Output 7-- B O Inverting Receiver Input and Inverting Driver Output 81 1 4V c c P w r +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

HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 CAUTION: ESD (Electrostatic Discharge) sensitive device. Permanent dama ge may occur on unconnected devices subject to high energy elect rostatic 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. ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the dev ice at these ratings or any other above those indicated in the operation sections to the specifications below is not implied. Ex posure to absolute maximum rating conditions for extended periods of time may affect re liability and cause permanent damage to the device. VCC +6.0V Input Voltage at control pins (RE, DE and DI) -0.5V to (V CC + 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

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.T Y P . M AX.U NITS CONDITIONS DRIVER DC CHARACTERISTICS VOD Differential Driver Output Vcc V No Load

2.0 R L = 100Ω (RS-422), Figure 3

1.5 R L = 54Ω (RS-485), Figure 3

1.5 V CM = -7V, Figure 4

1.5 V CM = +12V, Figure 4

∆VOD Change in Magnitude of Differential Output -0.20 0.20 V R L = 100Ω (RS-422), Figure 3, See note 1 -0.20 0.20 R L = 54Ω (RS-485), Figure 3, See note 1 -0.20 0.20 V CM = -7V, Figure 4, See note 1 -0.20 0.20 V CM = +12V, Figure 4, See note VOC 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 mA V OUT Forced to -7V, Figure 5 250 mA V OUT Forced to +12V, Figure 5

REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE VIH Logic Input Thresholds (DI, DE, RE)

2.0 V Logic Input High

VIL 0.8 V Logic Input Low VHYS Driver Input Hysteresis 100 mV T A = 25°C IIN Logic Input Current (DI, DE and RE)1 0 u A I N = 0 V -10 uA IN = Vcc Driver AC Characteristics freq Data Signaling Rate 32 Mbps 1/t UI, Duty Cycle 40 to 60% tPLH Driver Propagation Delay (low to High) 51 1 2 4 n s C L = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 tPHL Driver Propagation Delay (High to Low) 51 1 2 4 n s C L = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 tR Driver Rise Time 2.5 4.5 10 ns C L = 50pF, RL = 54Ω, freq = 8MHz, Figures 6 and 7 tF Driver Fall time 2.5 4.5 10 ns C L = 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 C L = 50pF, RL = 500Ω, Figures 8 and 9 tOZL Driver Enable to Outut Low 50 ns C L = 50pF, RL = 500Ω, Figures 10 and 11 tOHZ Driver Disable from Output High 50 ns C L = 50pF, RL = 500Ω, Figures 8 and 9 tOLZ Driver Disable from Output Low 50 ns C L = 50pF, RL = 500Ω, Figures 10 and 11 tOZV Shutdown to Driver Output Valid 6 us C L = 50pF, RL = 500Ω tSHDN Time to Shutdown 50 600 ns Note 2 and 3 RECEIVER DC CHARACTERISTICS IIN Input Current (A, B pins) -290 500 uA DE = 0, Vcc = 0 or 3.3V VA or VB = 12V, other input 0V VA or VB = -7V, other input 0V VIH Receiver Differential Thresholds (VA - VB) -85 -40 mV -7V ≤ VCM ≤ 12V, rising VIL -200 -125 mV -7V ≤ VCM ≤ 12V, falling Receiver Input Hysteresis 25 mV V CM = 0V VOH Receiver Output Voltage High 2.4 V I OUT = -8mA, VID = 200mV VOL Receiver Output Voltage Low 0.4 V I OUT = 8mA, VID = -200mV 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.T Y P . M AX.U NITS CONDITIONS

REV. 1.0.0 HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE NOTE: 1. Change in Magnitude of Dif ferential 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 assu red to be in shutdown. Note that the receiver and driver enable times increase during shutdown 3. Gauranteed by design and bench characterization. Thermal Shutdown Hysteresis 20 °C ESD Protection at Pins A, B, Y and Z +/-15 kV Human Body Model 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.T Y P . M AX.U NITS CONDITIONS

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 dr iver 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 agai nst 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 syst em IC’s may drive unpredictable values. Hot-swap capability prevents the SP349x E from driving any output signal until power has stabilized. After the initial power-up sequence, the hot-swap circuit becomes transp arent and driver enable and receiver enable resume their normal functions and timings

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)

HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0 PACKAGE DIMENSIONS (8 PIN NSOIC)

EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performanc e or reliability. EXAR Corp oration 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 in fringement. Charts and schedules cont ained 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 re commend the use of any of its products in life suppo rt 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) th e risk of injury or damage has been minimized; (b) th e user assumes all such ris ks; (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: uarttechsupport@exar.com. Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. SP3495E-3497E HIGH SPEED +3.3V RS-485/RS-422 TRANSCEIVERS WITH +/-15KV ESD PROTECTION AND ADVANCED FAILSAFE REV. 1.0.0

REVISION HISTORY

5/01/09 1.0.0 Production Release.