View ST485ACDR_4368128.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

march 2006 rev 2 1/19 19 order code part number temperature range package comments st485acn 0 to 70 c dip-8 50parts per tube / 40tube per box st485abn -40 to 85 c dip-8 50parts per tube / 40tube per box ST485ACDR 0 to 70 c so-8 (tape & reel) 2500 parts per reel st485abdr -40 to 85 c so-8 (tape & reel) 2500 parts per ree st485a very high speed low power rs-485/rs-422 transceiver general features low supply current: 5ma max high data rate > 30mbps designed for rs 485 interface applications -7 to 12 common mode input voltage range driver maintains high impedance in 3-state or with the power off 70mv typical input hysteresis operate from single 5 supply 4kv esd protection current limiting and thermal shutdown for driver overload protection latch-up free up to 500ma description the st485a is a low power, high speed transceiver for rs-485 and rs-422 communications. the device contains one driver and one receiver in half duplex configuration. the st485a draws 3ma (typ.) of supply current when unloaded or fully loaded with disabled drivers. it operates from a single 5v supply. driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that place the driver outputs into a high-impedance state. the receiver input has a fail-safe feature that guarantees a logic high output if both inputs are open circuit. the st485a is designed for bi-directional data communications or multipoint bus transmission lines. dip-8 so-8 www.st.com
contents st485a 2/19 contents 1 pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 truth tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1 logic input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.2 transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.3 receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.4 driver switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.5 receiver switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 test circuit and typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6 package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 7 revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
st485a pin configuration 3/19 1 pin configuration figure 1. pin configuration 1.1 pin description table 1. pin description pin n symbol name and function 1ro receiver output. if a>b by 200mv, ro will be high; if a truth tables st485a 4/19 2 truth tables note: x = don?t care; z = high impedance note: x = don?t care; z = high impedance table 2. truth table (driver) inputs outputs mode re de di b a a xhhlhnormal xhlhlnormal llxzznormal table 3. truth table (receiver) inputs outputs mode re de a-b ro ll -0.2v h normal ll -0.2v l normal l l inputs open h normal
st485a maximum ratings 5/19 3 maximum ratings note: absolute maximum ratings are those values beyond which damage to the device may occur. functional operation under these condition is not implied. table 4. absolute maximum ratings symbol parameter value unit v cc supply voltage 7 v v i control input voltage (re , de) -0.3 to 7 v v di driver input voltage (di) -0.3 to 7 v v do driver output voltage (a, b) -7.5 to 12.5 v v ri receiver input voltage (a, b) -7.5 to 12.5 v v ro receiver output voltage (ro) -0.3 to (v cc + 0.3) v
electrical characteristics st485a 6/19 4 electrical characteristics (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) ( note: 1 ) 4.1 logic input (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) ( note: 1 ) 4.2 transmitter (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) ( note: 1 ) table 5. dc electrical characteristics symbol parameter test conditions min typ max unit i supply v cc power supply current no load, v re =0v or v cc v de = v cc 2.3 5 ma v de = 0v 2.6 5 ma c i/o input/output capacitance 10 pf c ab driver output capacity 10 pf table 6. logic input electrical characteristics symbol parameter test conditions min typ max unit v il input logic threshold low de, di, re 0.8 v v ih input logic threshold high de, di, re 2 v i in1 logic input current de, di, re 2.0 a i in2 input current (a, b) v de =0v, v cc = 0 or 5.25v v in =12v 1 ma v in =-7v -0.8 ma table 7. transmitter electrical characteristics symbol parameter test conditions min typ max unit v od1 differential driver output (no load) 5 v v od2 differential driver output (with load) r l = 54 ? (rs-422) v cm = -7v to 12v 1.5 2.7 5 v ? v od change in magnitude of driver differential output voltage for complementary output states ( note: 1 ) r l = 27 ? or 50 ? 00.2v v oc driver common mode output voltage r l = 27 ? or 50 ? 13v ? v oc change in magnitude of driver common mode output voltage ( note: 1 ) r l = 54 ? or 100 ? 00.2v i osd driver short circuit output current v o = -7v to 12v 250 ma
st485a electrical characteristics 7/19 4.3 receiver (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) ( note: 1 ) 4.4 driver switching (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) (see note: 1 , 3 ) table 8. receiver electrical characteristics symbol parameter test conditions min typ max unit v th receiver differential threshold voltage v cm = -7v to 12v -0.2 0.2 v ? v th receiver input hysteresis v cm = 0v 70 mv v oh receiver output high voltage i out = -4ma, v id = 200mv 3.5 4.7 v v ol receiver output low voltage i out = 4ma, v id = -200mv 0.2 0.4 v i ozr 3-state (high impedance) output current at receiver v o = 0.4v to 2.4v 1 a r rin receiver input resistance v cm = -7v to 12v 12 24 k ? i osr receiver short-circuit current v o = 0v to v cc 795ma table 9. driver switching characteristics symbol parameter test conditions min typ max unit d r maximum data rate jitter < 5% 30 50 mbps t plh t phl propagation delay input to output r l = 54 ? , c l1 =c l2 =50pf, (figure 1) 18 30 ns t skew differential output delay skew r l = 54 ? , c l1 =c l2 =50pf, (figure 1) 0.5 2 ns t tlh t thl rise or fall differential time r l = 54 ? , c l1 =c l2 =50pf, (figure 1) 8 12 ns t pzl output enable time c l = 50pf, s1 closed 30 ns t pzh output enable time c l = 50pf, s2 closed 30 ns t phz output disable time c l = 15pf, s2 closed 30 ns t plz output disable time c l = 15pf, s1 closed 30 ns t sk(en) synchronous driver operation a-b at enable 2ns t sk(ds) synchronous driver operation a-b at disable 46ns
electrical characteristics st485a 8/19 4.5 receiver switching (v cc = 4.5v to 5.5v, t a = -40 to 85c, unless otherwise specified. typical values are referred to t a = 25c, v cc = 5v) (see note: 1 , 3 ) note: 1 all currents into device pins are positive; all currents out of device pins are negative; all voltages are referenced to device ground unless specified. 2 applies to peak current. see typical operating characteristics. 3t r =t f 6ms. table 10. driver switching characteristics symbol parameter test conditions min typ max unit t plh t phl propagation delay c l = 15pf 18 30 ns t rpds |t plh - t phl | propagation delay skew c l = 15pf 0.5 2 ns t pzl output enable time c rl = 15pf, s1 closed 7 12 ns t pzh output enable time c rl = 15pf, s2 closed 7 12 ns t phz output disable time c rl = 15pf, s2 closed 7 12 ns t plz output disable time c rl = 15pf, s1 closed 7 12 ns
st485a test circuit and typical characteristics 9/19 5 test circuit and typical characteristics figure 2. driver dc test load figure 3. receiver timing test load figure 4. driver/receiver timing test circuit
test circuit and typical characteristics st485a 10/19 figure 5. driver timing test load figure 6. driver timing test load figure 7. driver enable and disable time
st485a test circuit and typical characteristics 11/19 figure 8. receiver propagation delay figure 9. receiver enable and disable time
test circuit and typical characteristics st485a 12/19 figure 10. receiver output current vs. output voltage (output low) figure 11. receiver output current vs. output voltage (output high) figure 12. driver diff. output voltage vs common mode voltage (diff. output low) figure 13. driver diff. output voltage vs common mode voltage (diff. output low)
st485a test circuit and typical characteristics 13/19 figure 14. driver short circuit current vs line voltage (output high) figure 15. driver short circuit current vs. line voltage (output low) figure 16. receiver input current vs input voltage
package mechanical data st485a 14/19 6 package mechanical data in order to meet environmental requirements, st offers these devices in ecopack? packages. these packages have a lead-free second level interconnect. the category of second level interconnect is marked on the package and on the inner box label, in compliance with jedec standard jesd97. the maximum ratings related to soldering conditions are also marked on the inner box label. ecopack is an st trademark. ecopack specifications are available at: www.st.com
st485a package mechanical data 15/19 dim. mm. inch min. typ max. min. typ. max. a 3.3 0.130 a1 0.7 0.028 b 1.39 1.65 0.055 0.065 b1 0.91 1.04 0.036 0.041 b 0.5 0.020 b1 0.38 0.5 0.015 0.020 d 9.8 0.386 e 8.8 0.346 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 f 7.1 0.280 i 4.8 0.189 l 3.3 0.130 z 0.44 1.6 0.017 0.063 plastic dip-8 mechanical data p001f
package mechanical data st485a 16/19 dim. mm. inch min. typ max. min. typ. max. a 1.35 1.75 0.053 0.069 a1 0.10 0.25 0.04 0.010 a2 1.10 1.65 0.043 0.065 b 0.33 0.51 0.013 0.020 c 0.19 0.25 0.007 0.010 d 4.80 5.00 0.189 0.197 e 3.80 4.00 0.150 0.157 e 1.27 0.050 h 5.80 6.20 0.228 0.244 h 0.25 0.50 0.010 0.020 l 0.40 1.27 0.016 0.050 k ? (max.) ddd 0.1 0.04 so-8 mechanical data 0016023/c 8
st485a package mechanical data 17/19 dim. mm. inch min. typ max. min. typ. max. a 330 12.992 c 12.8 13.2 0.504 0.519 d 20.2 0.795 n 60 2.362 t 22.4 0.882 ao 8.1 8.5 0.319 0.335 bo 5.5 5.9 0.216 0.232 ko 2.1 2.3 0.082 0.090 po 3.9 4.1 0.153 0.161 p 7.9 8.1 0.311 0.319 tape & reel so-8 mechanical data
revision history st485a 18/19 7 revision history table 11. revision history date revision changes 28-mar-2006 2 order codes has been updated and new template.
st485a 19/19 please read carefully: information in this document is provided solely in connection with st products. stmicroelectronics nv and its subsidiaries ( st ) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described he rein at any time, without notice. all st products are sold pursuant to st s terms and conditions of sale. purchasers are solely responsible for the choice, selection and use of the st products and services described herein, and st as sumes no liability whatsoever relating to the choice, selection or use of the st products and services described herein. no license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. i f any part of this document refers to any third party products or services it shall not be deemed a license grant by st for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoev er of such third party products or services or any intellectual property contained therein. unless otherwise set forth in st ? s terms and conditions of sale st disclaims any express or implied warranty with respect to the use and/or sale of st products including without limitation implied warranties of merchantability, fitness for a particular purpose (and their equivalents under the laws of any jurisdiction), or infringement of any patent, copyright or other intellectual property right. unless expressly approved in writing by an authorize representative of st, st products are not designed, authorized or warranted for use in military, air craft, space, life saving, or life sustaining applications, nor in products or systems, where failure or malfunction may result in personal injury, death, or severe property or environmental damage. resale of st products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by st for the st product or service described herein and shall not create or extend in any manner whatsoev er, any liability of st. st and the st logo are trademarks or registered trademarks of st in various countries. information in this document supersedes and replaces all information previously supplied. the st logo is a registered trademark of stmicroelectronics. all other names are the property of their respective owners. ? 2006 stmicroelectronics - all rights reserved stmicroelectronics group of companies australia - belgium - brazil - canada - china - czech republic - finland - france - germany - hong kong - india - israel - ital y - japan - malaysia - malta - morocco - singapore - spain - sweden - switzerland - united kingdom - united states of america www.st.com

▲Up To Search▲

Price & Availability of ST485ACDR

	To Download ST485ACDR Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .