SP481R SIPEX | Alldatasheet
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Technical content
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation
FEATURES
■ Allows Over 400 Transceivers On A Transmission Line (1/10th Unit Load) ■ High Impedance on Receiver Inputs (RIN = 150kΩ typical) ■ Half-Duplex Configuration Consistent With Industry Standard Pinout ■ –7V to +12V Common Mode Input Voltage Range ■ Includes Shutdown Mode (ICC < 10µA) (For SP481R Only) ■ Low Power Consumption (250mW) ■ Separate Driver and Receiver Enable The SP481R and SP485R are pin-to-pin equivalent with our existing SP485 product and contain enhancements such as higher ESD tolerance and high receiver input impedance. The higher receiver input impedance allows for connecting over 400 transceivers on a single transmission line without degrading the RS-485 driver signal. Each device is packaged in an 8-pin plastic DIP or 8-pin narrow SOIC package. The SP481R offers a shutdown feature via the enable pins which will reduce the supply current (I CC) below 0.5µA typical. RO 1 RE 2 DE 3 DI 4
8 VCC
5 GND
D R SP485 Top View SP481R/SP485R 1/10th Unit Load RS-485 Transceiver Now Available in Lead Free Packaging
DESCRIPTION
TYPICAL APPLICATION CIRCUIT
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation Typically 25°C @ Vcc = +5V unless otherwise noted. MIN. TYP. MAX. UNITS CONDITIONS LOGIC INPUTS VIL 0.8 Volts VIH 2.0 Volts LOGIC OUTPUTS VOL 0.4 Volts I OUT= -3.2mA VOH 2.4 Volts I OUT= 1.0mA RS-485 DRIVER DC Characteristics TTL Input Levels V IL 0.8 Volts VIH 2.0 Volts Outputs Open Circuit Voltage 6.0 Volts Differential Output 1.5 5.0 Volts R L=54Ω, CL=50pF Balance ±0.2 Volts |V T| - |VT| Common-Mode Output 3.0 Volts Output Current 28.0 mA R L=54Ω Short Circuit Current ±250 mA Terminated in –7V to +12V AC Characteristics Maximum Data Rate 5 Mbps R L=54Ω Output Transition Time 30 ns Rise/fall time, 10%–90% Propagation Delay See Figures 3 and 5 t PHL 60 100 ns R DIFF=54Ω, CL1=CL2=100pF tPLH 60 100 ns R DIFF=54Ω, CL1=CL2=100pF Driver Output Skew 5 15 ns see Figure 3 and 5, tSKEW = | tDPLH - tDPHL | RS-485 RECEIVER DC Characteristics TTL Output Levels V OL 0.4 Volts VOH 2.4 Volts Tri-State Output Current ±1 µA 0.4V≤VOUT ≤2.4V; RE = VCC Inputs Common Mode Range –7.0 +12.0 Volts Receiver Sensitivity ±0.2 Volts –7V ≤ V CM ≤ +12V Input Impedance 120 150 k Ω –7V ≤ VCM ≤ +12V 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 of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. V Power Dissipation Package Derating: 8-pin Plastic DIP ø 8-pin Plastic N-SOIC
ELECTRICAL CHARACTERISTICS
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation RECEIVER INPUT GRAPH Typically 25°C @ Vcc = +5V unless otherwise noted. MIN. TYP. MAX. UNITS CONDITIONS AC Characteristics Maximum Data Rate 1 Mbps Propagation Delay See Figures 3 and 7 t PHL 1200 ns R DIFF=54Ω, CL1=CL2=100pF tPLH 1200 ns R DIFF=54Ω, CL1=CL2=100pF Differential Receiver Skew 60 ns | t PLH – tPHL |; RDIFF=54Ω, CL1=CL2=100pF, see Figures 3 and 7 SHUTDOWN TIMING (SP481R) Time to Shutdown 50 600 ns RE = V CC, DE = 0V RS-485 Driver Enable Time See Figures 4 and 6 Enable to Low 40 500 ns C L=15pF, S1 Closed Enable to High 40 500 ns C L=15pF, S2 Closed Disable Time See Figures 4 and 6 Disable From Low 40 500 ns C L=15pF, S1 Closed Disable From High 40 500 ns C L=15pF, S2 Closed RS-485 Receiver Enable Time See Figures 2 and 8 Enable to Low 40 500 ns C L=15pF, S1 Closed Enable to High 40 500 ns C L=15pF, S2 Closed Disable Time See Figures 2 and 8 Disable From Low 40 500 ns C L=15pF, S1 Closed Disable From High 40 500 ns C L=15pF, S2 Closed POWER REQUIREMENTS Supply Voltage VCC +4.75 +5.25 Volts Supply Current ICC No Load 300 500 µA RE = VCC or 0V, DE = 0V No Load 500 900 µA RE = VCC or 0V, DE = VCC Supply Current in Shutdown 0.5 10 µA RE = VCC, DE = OV ENVIRONMENTAL Operating Temperature Commercial (..C..) 0 +70 °C Industrial (..E..) –40 +85 °C Storage Temperature –65 +150 °C -7V -3V +6V +12V -60µA +100µA 1/10 Unit Load Maximum Input Current versus voltage. (Shaded region) SP485R Reciever -7V -3V +6V +12V -0.6 mA +1.0mA
1 Unit Load
versus voltage. (Shaded region) Standard SP485R Reciever
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation with the two 125Ω cable termination resistors on each end. The receiver contains a enable pin (RE) which enables the receiver when a logic LOW is asserted. A logic HIGH will tri-state the receiver output and the inputs will maintain at least 120kΩ impedance. The receiver can operate to at least 1Mbps. The receiver also contains a fail-safe feature which outputs a logic HIGH when the inputs are open as in a disconnected cable. SHUTDOWN MODE The SP481R includes a shutdown function to reduce power consumption. The shutdown is activated by simultaneously applying a logic LOW to DE and a logic HIGH to RE. While in the shutdown mode, the power supply current is typically less than 1µA. The driver outputs are disabled and are at a high impedance state determined by the receiver input impedance which should be at least 120kΩ. The receiver output is at also at high impedance during shutdow. Output leakage current when the receiver is disabled is under 1µA. GENERAL DESCRIPTION The SP485R is a low power RS-485 differential transceiver. Similar to the SP485, the SP485R contains a half-duplex driver and receiver with tri-state control. However, the SP485R is in- tended for increased connections on a single bus compared to the orignal RS-485 specification. The RS-485 standard is ideal for multi-drop applications where one bus can contain many drivers and/or receivers. The RS-485 standard implementation allows up to 32 transceivers to be connected on to the data bus. RS-485 is also specified for driving higher speeds over long cable lengths of up to 4,000 feet. The SP485R and SP481R exceed the standard b allowing up to 400 receivers to share a bus. DRIVERS The driver output complies with the RS-485 electrical characteristics as specified by the standard. The output swings from 0V to V CC and maintains greater than +1.5V with a 54Ω load attached between the two outputs. In adhering to the RS-485 specification, the driver outputs inherently comply with the RS-422 standard. With a load of 100Ω between the two outputs, the driver can sustain at least +2.0V. The driver contains an enable pin (DE) which tri-states the output when DE is a logic LOW. The outputs during the tri-stated condition are at a high impedance (>100kΩ). A logic HIGH enables the driver for normal operation. The driver can operate to at least 5Mbps. RECEIVERS The SP485R receiver has differential inputs with an input sensitivity of lower than ±200mV. As mentioned above, the RS-485 specification allows up to 32 transceivers on a the same bus. The SP485R allows over 400 transceivers on the same bus due to the high input impedance of at least 120kΩ. This higher capacity allows more components to be attached to the same bus without degrading the signal quality. The drivers are still able to drive an equivalent 54Ω from the 320 transceivers with an input impedance of at least 120kΩ in parallel along
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation PACKAGE: 8 PIN PDIP INDEX AREA b N 1 23 N/2 c - - .210 .015 - Dimensions in inches8 PIN PDIP JEDEC MS-001 (BA) Variation .115 .130 .195 .014 .018 .022 .045 .060 .070 .240 .250 .280 A b c E e eA eB .115 .130 .150L MIN NOM MAX b3 .030 .039 .045 D .008 .010 .014 .355 .365 .400 .005 .300 .310 .325 .100 BSC .300 BSC .430 - - eA eB E c
8 PIN PDIP
D A L b e
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation PACKAGE: 8 PIN NSOIC SEE VIEW C Ø 1.65 DIMENSIONS Minimum/Maximum (mm)
8 Pin NSOIC
(JEDEC MS-012, AA - VARIATION) COMMON HEIGHT DIMENSION A b c L e E 1.35
4.90 BSC
0.40 0.31 0.51 SYMBOL MIN NOM MAX 0.10 - 0.25 D 1.75 1.25 0.17 0.25
6.00 BSC
3.90 BSC
1.27 BSC
1.27
1.04 REF
0.25 BSC
15º A A2 SEATING PLANE SIDE VIEW L ØØ1 Seating Plane Gauge Plane VIEW C TOP VIEW e E E/2 A INDEX AREA (D/2 X E1/2) E1/2 D b
8 PIN NSOICPACKAGE:
c WITH PLATING BASE METAL b CONTACT AREA
Date: 6/21/04 SP485R RS-485 Serial Transceiver © Copyright 2004 Sipex Corporation Part Number Temperature Range Package Types Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability aris ing out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor t he rights of others. Corporation ANALOG EXCELLENCE Available in lead free packaging. To order add “-L” suffix to part number. Example: SP485REN/TR = standard; SP485REN-L/TR = lead free /TR = Tape and Reel Pack quantity is 2,500 for NSOIC. Sipex Corporation Headquarters and Sales Office
233 South Hillview Drive
Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600
ORDERING INFORMATION
6/21/04 A Added extended temp range and tape and reel part numbers. Updated packaging specs.