SP4082E EXAR | Alldatasheet

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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007

DESCRIPTION

FEATURES

APPLICATIONS

5V RS-485/RS-422 Transceivers 1/8th Unit Load, Slew-Rate Limited, ±15kV ESD-Protected

  • 5.0V single supply operation
  • Receiver failsafe on open or shorted lines
  • /8th Unit Load, 256 transceivers on bus
  • Robust ESD protection for RS-485 pins ±5kV Human Body Model
  • Controlled driver slew rates 5kbps, Low EMI
  • Driver short circuit current limit and thermal shutdown for overload protection
  • Industry standard package footprints
  • Motor Control
  • Building Automation
  • Security Systems
  • Remote Meter Reading
  • Long or un-terminated transmission lines The SP4082E is designed for reliable, bidirectional communication on multipoint bus transmission lines. The device contains one differential driver and one differential receiver. It is a half-duplex de - vice. The device complys with TIA/EIA-485 and TIA/EIA-422 standards. Lead-free and RoHS compli- ant packages are available. This device is ruggedized for use in harsh operating conditions over the entire common-mode volt - age range from -7V to +2V. Receivers are specially designed to fail-safe to a logic high output state if the inputs are un-driven or shorted. All RS-485 bus-pins are protected against severe ESD events 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 to +85ºC) operating temperatures. Receivers have exceptionally high input impedance, which places only /8th the standard load on a shared bus. Up to 256 trans- ceivers may coexist while preserving full signal margin. The device operates from a single 5.0V power supply and draws negligible quiescent power. The device has an independent enable and disable for the driver and receiver and will enter a low power shutdown mode if both driver and receiver are disabled. All outputs maintain high impedance during shutdown or when powered-off.

8 PIN NSOIC

A B VccRO RE DE DI

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 PIN ASSIGNMENTS Pin Number Pin Name Pin Function RO Receiver Output. When RE is low and if (A – B) ≥ -40mV, RO is high. If (A – B) ≤ - 200mV, RO is low.

2 REREREE

Receiver Output Enable. When RE is low, RO is enabled. When RE is high, RO is high impedance. Drive RE high and DE low to enter shutdown mode. 3 DE Driver Output Enable. When DE is high, outputs are enabled. When DE is low, outputs are high impedance. Drive DE low and RE high to enter shutdown mode. 4 DI Driver Input. With DE high, a low level on DI forces non- inverting output low and inverting output high. A high level on DI forces non-inverting output high and inverting output low.

5 GND Ground

6 A Non-inverting Receiver Input and Non-inverting Driver Output

7 B Inverting Receiver Input and Inverting Driver Output

8 Vcc Positive Supply VCC. Bypass to GND with a 0.uF capacitor. D R A B RO GND DE VCC RE DI 8-Pin Half Duplex8-Pin Half Duplex DEVICE ARCHITECTURE AND BLOCK DIAGRAMDEVICE ARCHITECTURE AND BLOCK DIAGRAM

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 ABSOLUTE MAxIMUM RATINGS RECOMMENDED OPERATING CONDITIONS These are stress ratings only and functional opera - tion of the device at these ratings or any other above those indicated in the operation sections of the speci- fications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Package Power Dissipation: Maximum Junction Temperature 50°C 8-Pin SO Øja = 28.4°C/W Recommended Operating Conditions Min. Nom. Max. Unit Supply Voltage, Vcc 4.5 5 5.5 V Input Voltage on A and B pins -7 2 V High-level input voltage (DI, DE or RE), Vih 2 Vcc V Low-level input voltage (DI, DE or RE), Vih 0 0.8 V Output Current Driver -60 60 mA Receiver -8 8 Operating Free Air Temperature, Ta Industrial Grade (E) -40 85 °C Note: The least positive (most negative) limit is designated as the maxium value. Vcc=5V ±5%, Tmin to Tmax, unless otherwise noted, Typical values are Vcc=5V and Ta=25°C

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007

ELECTRICAL CHARACTERISTICS

PARAMETER TEST CONDITIONS MIN TYP MAx UNIT Digital Input Signals: DI, DE, RE Logic input thresholds High, Vih 2.0 V Low, Vil 0.8 Logic Input Current Ta = 25°C, after first transition ± μA Input Hysteresis Ta = 25°C 00 mV Driver Differential Driver Output (Vod) No Load Vcc V Differential Driver Output, Test Rl=100Ω (RS-422) 2 Vcc VRl=54Ω (RS-485) .5 2.7 Vcc Differential Driver Output, Test 2 Vcm = -7 to +2V .5 Vcc Change in Magnitude of Differential Output Voltage (ΔVod) (Note ) Rl=54 or 100Ω ±0.2 V Driver Common Mode Output Voltage (Voc) Rl=54 or 100Ω 3 V Change in Common Mode Output Voltage (ΔVoc) Rl=54 or 100Ω ±0.2 V Driver Short Circuit Current Limit -7V ≤ Vout ≤ +12V ±250 mA Output Leakage Current DE=0, Vout=2V 25 μARE=0, Vcc=0 or 5.5V Vout= -7V -00 Receiver Receiver Input Resistance -7V ≤ Vcm ≤ 12V 96 KΩ Input Current (A, B pins) DE=0, RE=0, Vcc=0 or 5.5V Vin= 2V 25 Vin= -7V -00 μA Receiver Differential Threshold (VA-VB) -7V ≤ Vcm ≤ 12V -200 -25 -40 mV Receiver Input Hysteresis 25 mV Receiver Output Voltage Voh Iout = -8mA, Vid = -40mV Vcc-.5 V Vol Iout = 8mA, Vid = -200mV 0.4 High-Z Receiver Output Current Vcc =5.5V, 0 ≤ Vout ≤ Vcc ± μA Receiver Output Short Circuit Current 0V ≤ Vro ≤ Vcc ± 95 mA Supply and Protection Supply Current IQ, Active Mode No load, DI=0 or Vcc 400 900 μA Shutdown Mode, Note 2 DE=0, RE=Vcc, DI=Vcc μA Thermal Shutdown Temperature Junction temperature 65 oC Thermal Shutdown Hysteresis 5 Notes: . 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. If the inputs are in this state for less than 50ns the device does not enter shutdown. If the enable inputs are held in this state for at least 600ns the device is assured to be in shutdown. In this low power mode most circuitry is disabled and supply current is typically nA. 3.Characterized, not 00% tested.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 TIMING CHARACTERISTICS DRIVER CHARACTERISTICS: Conditions Min. Typ. Max. Unit Data Signaling Rate ( / tUI) Duty Cycle 40 to 60% 5 Kbps Driver Propagation Delay (tPHL, tPLH) RL = 54Ω, CL = 50pF, 3500 ns Driver Output Rise/Fall Time (tR, tF) 667 200 2500 ns Driver Differential Skew (tPLH – tPHL) ±500 ns Driver Enable to Output High (tDZH) 3500 ns Driver Enable to Output Low (tDZL) 3500 ns Driver Disable from Output High (tDHZ) 00 ns Driver Disable from Output Low (tDLZ) 00 ns Shutdown to Driver Output Valid (tDZV) 6000 ns RECEIVER CHARACTERISTICS: Conditions Min. Typ. Max Unit Receiver Propagation Delay CL = 5pF, VID = ±2V 250 ns Prop. Delay Skew (tPLH – tPHL) ±50 ns Receiver Output Rise / Fall Time (tR, tF) CL = 5pF 50 ns Receiver Enable to Output High (tZH) 00 ns Receiver Enable to Output Low (tZL) 00 ns Receiver Disable from Output High (tHZ) 00 ns Receiver Disable from Output Low (tLZ) 00 ns Shutdown to Receiver Output Valid (tROV) 3500 ns Time to Shutdown (Note 2,3) 50 600 ns Unless otherwise noted Vcc= +5.0±0.5V, ambient temperature TA from -40 to +85ºC

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 Driver DC Test Circuit Receiver DC Test Circuit Driver Propagation Delay Time Test Circuit and Timing Diagram

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 DDI= 0 or VCC DE= 3V A/Y B/Z DI D Y Z S 0 or VCC GENERATOR 50½ CL=50pF OUT RL= 500½ DE OUT VCC /2 VCC 0.25V tLZ tZL, tZL(SHDN) VOM = (VOL + VCC)/2 Driver Differential Output Test Circuit Driver Enable and Disable Times Test Circuit and Timing Diagram

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007

0 OR VCC DI D

Y Z 50½ CL=50pF S VCC OUT RL=500½ VCC VCC/2 tLZ tZL, tZL(SHDN) 0.25VVOM = (VOL+ VCC)/2 VOL VCC OUT DE VID RE A B R OUT CL 5pF A B OUT tPHL .5V tPLH VOH VOL Receiver Propagation Delay Test Circuit and Timing Diagram

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 .5V -.5V GENERATOR S3 B A RE 50½ CL=5pF S VCC RE .5V tZH, tZH(SHDN) OUT VOH VOH/2 S is open, S2 is closed, S3=.5V S is closed, S2 is open, S3= -.5V RE OUT VOL = VCC/2 VOL VCC .5V tZL, tZL(SHDN) S is open, S2 is closed, S3=.5V RE 0.25V OUT .5V VOH S is closed, S2 is open, S3= -.5V RE OUT .5V tLZ VCC VOL0.25V Receiver Enable and Disable Times Test Circuit Receiver Enable and DisableTiming Diagram

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 FUNCTION TABLES Transmitting Inputs Outputs RE DE DI A B X 0 X 0 0 0 0 X High-Z

0 X Shutdown

0 X ≥ -40mV

0 X ≤-200mV 0

0 X Open/shorted

Note: Receiver inputs -200mV < VA - VB < -40mV, should be considered indeterminate

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 Note: Receiver inputs -200mV < VA - VB < -40mV, should be considered indeterminate The SP4082E is a 5V half-duplex RS-485 trans- ceiver. The SP4082E contains one driver and one re - ceiver. These devices feature fail-safe circuitry that will guarantee a logic-high receiver output when the receiver inputs are open or shorted. The SP4082E features reduced slew-rate driv - ers that minimize EMI and reduce reflections caused by improperly terminated cables, allow- ing error-free data transmission up to 5kbps. It operates from a single 5.0V supply. Drivers are output short-circuit current limited. Ther - mal-shutdown circuitry protects drivers against excessive power dissipation. When activated, the thermal-shutdown circuitry places the driver outputs into a high-impedance state. Receiver FAILSAFE Ordinary RS-485 differential receivers will be in an indeterminate state whenever A - B is less than ±200mV. This situation can occur when - ever the data bus is not being actively driven. The Failsafe feature guarantees a logic-high re- ceiver output if the receiver’s differential inputs are shorted or open-circuit. The receiver thresholds of the SP4082E are very precise and offset by at least a 40mV noise margin from ground. This results in a logic-high receiver output at zero volts input differential while maintaining compliance with the EIA/TIA- 485 standard of ±200mV. ±15KV ESD PROTECTION ESD-protection structures are incorporated on all pins to protect against electrostatic discharg- es encountered during handling and assembly. The driver output and receiver inputs have ex - tra protection against static electricity. Sipex uses state of the art structures to protect these pins against ESD of ±5kV without damage. The ESD structures withstand high ESD in all states: normal operation, shutdown, and pow - ered down. After an ESD event, the SP4082E keeps working without latch-up or damage. ESD protection can be tested in various ways. The transmitter outputs and receiver inputs of the SP4082E is characterized for protection to the following limits: ±5kV using the Human Body Model ESD TEST CONDITIONS ESD performance depends on a variety of con- ditions. Contact Sipex for a reliability report that documents test setup, methodology and results. 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 imped - ance is 12kΩ (1 unit load). A standard driver can drive up to 32 unit loads. The SP4032E has only a /8th unit load receiver input impedance (96kΩ), thereby allowing eight times as many, up to 256, transceivers to be connected in par - allel 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 bring- ing both RE high and DE low simultaneously. While in shutdown devices typically 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 shut down. The drivers and receivers take longer to become enabled from low power shut- down mode tZL(SHDN) and tZL(SHDN) than from driver/receiver-disable mode (tZH, tZL). DRIVER OUTPUT PROTECTION Two mechanisms prevent excessive output cur- rent and power dissipation caused by faults or by bus contention. First, a driver current limit on the output stage provides immediate protec-

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 tion against short circuits over the whole com - mon-mode voltage range. Second, a thermal- shutdown circuit forces the driver outputs into a high-impedance state if junction temperature becomes excessive. LINE LENGTH, EMI, AND REFLECTIONS It features controlled slew-rate drivers that mini- mize EMI and reduce reflections caused by im - properly terminated cables. Driver rise and fall times are limited to no faster than 667ns, allowing error-free data transmis - sion up to 5kbps. The RS-485/RS-422 standard covers line lengths up to 4,000ft. Maximum achievable line length is a function of signal attenuation and noise. Use of slew-controlled drivers may help to reduce crosstalk interference and permit communication over longer transmission lines. Termination prevents reflections by eliminating the impedance mismatches on a transmission line. Line termination is typically used if rise and fall times are shorter than the round-trip signal propagation time. Slew-limited drivers may re - duce or eliminate the need for cable termination in many applications. H alf -D uplex N etwork TYPICAL APPLICATIONS: Half-Duplex Network

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 T T T TT TTT T

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (50)6687000 • Fax (50)668-707 • www.exar.com SP4082E_00_22007 Notice EXAR Corporation reserves the right to make changes to any products contained in this publication in order to improve design, performance or reliabil- ity. EXAR Corporation assumes no representation that the circuits are free of patent infringement. Charts and schedules contained herein 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 writting, 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 2007 EXAR Corporation Datasheet December 2007 Send your Interface technical inquiry with technical details to: customersupport@exar.com Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.

ORDERING INFORMATION

Part number LEAD FREE Tape & Reel Temperature range Package Type SP4082EEN -L /TR From -40 to +850C 8 pin nSOIC All packages are available as lead free (RoHS compliant). To order add “-L” suffix to part number. For Tape and Reel add “/TR”. Reel quantity is 2,500 for NSOIC. Example: SP4082EEN-L/TR = lead free and Tape and Reel. SP4082EEN/TR = standard with Tape and Reel.