SP V Low Power RS-485/RS-422 Transceiver RO 1 VCC RE 2 DE 3 DI 4 GND. Description. Block Diagram

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1 3. Low Power S-485/S-4 Transceiver escription The SP3494 device is a 3. low power half-duplex transceiver that meets the specifications of the S-485 and S-4 serial protocols. This device is pin-to-pin compatible with the MaxLinear SP3481 device as well as other popular industry standards. The SP3494 features the MaxLinear BiCMOS process, allowing low power operation without sacrificing performance. The partially slew-rate limited drivers minimize EMI and reduce reflections caused by improperly terminated cables allowing error-free data transmission. The SP3494 is a halfduplex partially slew-rate limited transceiver that will deliver a data transmission rate up to.5mbps. The SP3494 is equipped with a lowpower shutdown mode and driver/receiver high-z enable lines. FEATUES Operates from a single 3. supply Interoperable with 5. logic ±00mV receiver input sensitivity -7V to +1V common-mode input voltage range Allows up to 3 transceivers on the serial bus river/receiver enable lines 10μA low-power shutdown mode Compatibility with the MAX3486 and industry standard pinout Ordering Information - Back Page Block iagram O 1 8 E 7 B E 3 6 A I 4 5 GN SP3494 1/9

2 Absolute Maximum atings 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 CC Input Voltages Output Voltages rivers to 6. eceivers...±14v rivers...+/-14v eceivers to 6. Storage Temperature C to +150 C Maximum Junction Temperature, T J...15 C Power issipation 8-pin NSOIC mW (derate 6.90mW/ C above +70 C) Operating Conditions Package Power issipation 8-pin NSOIC Ѳ JA C/W ES ating Human Body Model (HBM)... ±kv Electrical Characteristics T AMB = T MIN to T MAX and V CC = 3. ±5% unless otherwise noted. PAAMETES MIN. TYP. MAX. UNITS CONITIONS SP3494 river C Characteristics ifferential output voltage Vcc V Unloaded; = Ω ; Figure 1 ifferential output voltage Vcc V With load; = (S-4); Figure 1 ifferential output voltage 1.5 Vcc V With load; = 7Ω (S-485); Figure 1 Change in magnitude of driver differential output voltage for complimentary states 0. V = 7Ω or = ; Figure 1 river common-mode output voltage 3 V = 7Ω or = ; Figure 1 Input high voltage.0 V Applies to E, I, E Input low voltage 0.8 V Applies to E, I, E Input current ±10 µa Applies to E, I, E river short circuit current V out = HIGH river short circuit current V out = LOW SP3494 river AC Characteristics ±50 ma -7V V O +1V; Figure 8 ±50 ma -7V V O +1V; Figure 8 Maximum data rate.5 Mbps E = V CC, E = V CC river input to output, t plh ns Figures & 9 river input to output, t phl ns Figures & 9 ifferential driver skew 10 ns t O1 - t O, Figures and 10 river rise or fall time ns From 10%-90%; Figures 3 and 10 /9

3 Electrical Characteristics (Continued) T AMB = T MIN to T MAX and V CC = 3. ±5% unless otherwise noted. PAAMETES MIN. TYP. MAX. UNITS CONITIONS SP3494 river AC Characteristics (Continued) river enable to output high 5 10 ns Figures 4 and 11 river enable to output low ns Figures 5 and 11 river disable time from low ns Figures 5 and 11 river disable time from high ns Figures 4 and 11 SP3494 eceiver C Characteristics ifferential input threshold Volts -7V V CM 1V Input hysteresis 0 mv V CM = Output voltage HIGH Vcc-0.4 Volts V I = +00mV, -1.5mA Output voltage LOW 0.4 Volts V I = -00mV,.5mA Three-state (high impedance) output current ±1 µa V O V CC ; E = V CC Input resistance 1 15 kω -7V V CM 1V Input current (A, B); V IN = 1V 1.0 ma E =, V CC = or 3.6V, V IN = 1V Input current (A, B); V IN = -7V -0.8 ma E =, V CC = or 3.6V, V IN = -7V Short circuit current 7 60 ma V CM V CC SP3494 eceiver AC Characteristics Maximum data rate.5 Mbps E =, E = eceiver input to output, t PLH ns Figures 6 and 1 eceiver input to output, t PHL ns Figures 6 and 1 ifferential receiver skew 10 ns t SKEW = t PHL - t PLH, Figures 6 and 1 eceiver enable to output low ns Figures 7 and 13, S 1 closed, S open eceiver enable to output high ns Figures 7 and 13, S closed, S 1 open eceiver disable from low ns Figures 7 and 13, S 1 closed, S open eceiver disable from high ns Figures 7 and 13, S closed, S 1 open 3/9

4 Electrical Characteristics, Continued T AMB = T MIN to T MAX and V CC = 3. ±5% unless otherwise noted. PAAMETES MIN. TYP. MAX. UNITS CONITIONS SP3494 Shutdown Timing Time to shutdown ns E = 3., E = river enable from shutdown to output high river enable from shutdown to output low eceivers enabled from shutdown to output high eceivers enabled from shutdown to output low ns Figures 4 and ns Figures 5 and ns ns Figures 7 and 13, S closed, S 1 open Figures 7 and 13, S 1 closed, S open Power equirements Supply current, no load µa E, I = or V CC ; E = V CC Supply current, no load µa E =, I = or V CC, E = Shutdown mode 10 µa E =, E = V CC Pin Functions Pin Number Pin Name escription O 1 E 8 7 B 1 O eceiver output E eceiver Output Enable Active LOW 3 E river Output Enable Active HIGH 4 I river Input E 3 I A GN 5 GN Ground Connection 6 A 7 B Non-Inverting river Output / eceiver Input Inverting river Output / eceiver Input 8 Positive Supply 3. ±5% SP3494 Pinout (Top View) 4/9

5 Test Circuits VM Vcc V O Figure 1. river C Test Load Circuit V OC Figure. river Propagation elay Test Circuit S1 + VOL = L = 7Ω C L = 15pF (NOTE ) S1 C L L = 60Ω CL = 50pF (NOTE ) L = 110Ω C L = 15pF (NOTE ) Figure 3. river ifferential Output elay and Transition Time Circuit. = + VOL Figure 4. river Enable and isable Timing Circuit, Output High O S1 L = 110Ω V I CL = 15pF (NOTE ) C L = 50pF (NOTE ) Figure 5. river Enable and isable Timing Circuit, Output Low = Figure 6. eceiver Propagation elay Test Circuit - S3 VI 1k CL = 15pF (NOTE ) S1 S E = 0 or Vcc I = 0 or Vcc A/Y B/Z IOS 100Ω -7V to +1V V Figure 7. eceiver Enable and isable Timing Circuit Figure 8. river Short Circuit Current Limit Test NOTES 1: The input pulse is supplied by a generator with the following characteristics: P = 50kHz, 50% duty cycle, t < 6.0ns, Z O =. : C L includes probe and stray capacitance. 5/9

6 Switching Waveforms INPUT IN tplh tphl Y PUT to1 to Z PUT VOL tphl tplh 90% 90% 50% 50% 10% 10%. -. VOL tt tt = + VOL Figure 9. river Propagation elay Waveforms Figure 10. river ifferential Output elay and Transition Time Waveforms E PUT HIGH tpzh tphz 0.5V INPUT tplh tphl PUT LOW VOL tpzl tplz 0.5V PUT = + VOL Figure 11. river Enable and isable Timing Waveforms = Figure 1. eceiver Propagation elay Waveforms E PUT S1 is open S is closed S3 = tphz 10% tpzh tpsh E PUT VOL S1 is closed S is open S3 = - 10% tplz tpzl tpsl Figure 13. eceiver Enable and isable Waveforms 6/9

7 escription The SP3494 is a 3. low power half-duplex transceiver that meets the electrical specifications of the S-485 and S-4 serial protocols. This device is pin-to-pin compatible with the MaxLinear SP3481 and SP481 devices as well as popular industry standards such as the MAX3486 and the The SP3494 feature Maxlinear s BiCMOS process allowing low power operation without sacrificing performance. The SP3494 has a partially slew rate limited driver with a data transmission rate of.5mbps. river The driver outputs of the SP3494 are differential outputs. The typical voltage output swing with no load will be 0 volts to V CC. With worst case loading of 54Ω across the differential outputs, the driver can maintain greater than voltage levels. The SP3494 driver has an enable control line which is active HIGH. A logic HIGH on E (pin 3) will enable the differential driver outputs. A logic LOW on the E (pin 3) will force the driver outputs to high impedance (high-z). The SP3494 driver will operate up to.5mbps. In addition to adhering to the 50mA I SC maximum limit on the driver output, the driver output short-circuit protection will allow the device to withstand an infinite short circuit over the -7. to 1V common mode range without damage. INPUTS E E I LINE CONITION PUTS X 1 1 No Fault 0 1 X 1 0 No Fault 1 0 X 0 X X Z Z Table 1. Transmit Function Truth Table B A eceiver The receiver has differential inputs with an input sensitivity of ±00mV. Input impedance of the receiver is typically 15kΩ (1kΩ minimum). A wide common mode range of -7V to 1V allows for large ground potential differences between systems. The receiver is equipped with a fail-safe feature which guarantees that the receiver output will be in a high state when the input is left unconnected. The receiver of the SP3494 operate up to.5mbps. The receiver of the SP3494 has an enable control line which is active LOW. A logic LOW on E (pin ) of the SP3494 will enable the differential receiver. A logic HIGH on E (pin ) will disable the receiver. The SP3494 is equipped with a shutdown mode. To enable the shutdown state, both the driver and receiver must be disabled simultaneously. A logic LOW on E (pin 3) and a logic HIGH on E (pin ) will put the SP3494 into shutdown. In shutdown, the supply current will drop to less than 10µA. INPUTS PUTS E E A - B V V Inputs Open X Z Table. eceive Function Truth Table 7/9

8 Mechanical imensions NSOIC8 Top View Side View Front View rawing No: evision: A PO /9

9 Ordering Information (1) Part Number Operating Temperature ange Lead-Free Package Packaging Method SP3494CN-L/T 0 C to 70 C eel SP3494EN-L SP3494EN-L/T -40 C to 85 C Yes () 8-pin NSOIC Tube eel NOTE: 1. efer to for most up-to-date Ordering Information.. Visit for additional information on Environmental ating. evision History evision ate escription 10/15/0 -- Legacy Sipex atasheet 07/10/ /07/ Convert to Exar Format. Update ordering information and add new Figure 8 - river Short Circuit Current Limit Test Circuit. emove EOL device SP3493. Update to MaxLinear logo. emove GN from ifferential Output Voltage min (page ), correct part number (SP3485 eceiver, page 3). Added maximum junction temperature, package power dissipation and ES rating. Update format and ordering information table. Corporate Headquarters: 5966 La Place Court Suite 100 Carlsbad, CA 9008 Tel.:+1 (760) Fax: +1 (760) High Performance Analog: 4870 Kato oad Fremont, CA Tel.: +1 (510) Fax: +1 (510) serialtechsupport@exar.com The content of this document is furnished for informational use only, is subject to change without notice, and should not be construed as a commitment by MaxLinear, Inc.. MaxLinear, Inc. assumes no responsibility or liability for any errors or inaccuracies that may appear in the informational content contained in this guide. Complying with all applicable copyright laws is the responsibility of the user. Without limiting the rights under copyright, no part of this document may be reproduced into, stored in, or introduced into a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), or for any purpose, without the express written permission of MaxLinear, Inc. Maxlinear, Inc. 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 MaxLinear, Inc. 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 MaxLinear, Inc. is adequately protected under the circumstances. MaxLinear, Inc. may have patents, patent applications, trademarks, copyrights, or other intellectual property rights covering subject matter in this document. Except as expressly provided in any written license agreement from MaxLinear, Inc., the furnishing of this document does not give you any license to these patents, trademarks, copyrights, or other intellectual property. Company and product names may be registered trademarks or trademarks of the respective owners with which they are associated. 017 MaxLinear, Inc. All rights reserved SP3494_S_ /9