View TDA747811_7619287.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

june 2011 doc 10679 rev 3 1/11 11 tda7478 single chip rds demodulator features very high rds demodulation quality with improved digital signal processing high performance, 57 khz bandpass filter (8th order) filter adjustment free and without external components purely digital rds demodulation without external components rds signal quality output 4.332 mhz crystal oscillator (8.664 mhz optional) low noise cmos technology low radiation description the tda7478 recovers the additional inaudible rds information which is transmitted by fm radio broadcasting stations and operates in accordance with the ebu (european broadcasting union) specifications. the device is made up of two sections: a cascaded antialiasing + switched capacitors 8 th bandpass filter for precise rds band selection and a demodulating section that performs the extraction od rds data stream (rdda) and clock (rdcl), to be further processed by a suitable rds decoder. output for rds signal quality is also present. '!0'03 tssop16 table 1. device summary order code package packing e-tda7478ad tssop16 tube e-tda7478adtr tape and reel www.st.com
contents tda7478 2/11 doc 10679 rev 3 contents 1 block diagram and pins descripti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 pins description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1 thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3 output timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 oscillator controls (fsel, osel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6 revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
tda7478 block diagram and pins description doc 10679 rev 3 3/11 1 block diagram and pins description 1.1 block diagram figure 1. block diagram '!0'03 nd/2$%2 !.4)!,)!3).' &),4%2 th/2$%2 3# "!.$0!33 &),4%2 -08 p& &),/54 6 3 62%& n& m & /3#),,!4/2 $)6)$%2 +(z0,, 0/,!2)49 ")0(!3%$%# ).4%'2!, ")0(!3%$%# (z 0,, -58 $)&&$%#/$%2 4%34,/')# 15!,$%4 '.$ %842%3 4- 2$$! 15!, .5 2$#, &3%, /3%, /3#/54 /3#). -(z #p& #p& 4
block diagram and pins description tda7478 4/11 doc 10679 rev 3 1.2 pins description figure 2. pin connection (top view) table 2. pins description pin # name description 1 qual output for signal quality indication (high = good) 2 rdda rds data output 3 vref reference voltage 4 mpx rds input signal 5 osel oscillator selector pin: ? open, closed to v s = quartz oscillator ? closed to gnd = external driven 6 gnd ground 7 n.u. not used (to be left open) 8 filout filter output 9 fsel frequency selector pin: ? open = 4.332 mhz ? closed to vs = 8.664 mhz 10 tm test mode pin: ? open = normal operation ? closed to vs = testmode 11 extres reset pin: ? open = run mode ? closed to vs = reset condition 12 v s supply voltage 13 oscin oscillator input 14 oscout oscillator output 15 t57 testing output pin: 57 khz clock output 16 rdcl rds clock output 1187.5 hz '!0'03 15!, 2$$! 62%& -08 /3%, .5 '.$ 4- 6 3 %842%3 /3#). /3#/54 4 2$#, &),/54 &3%,
tda7478 electrical specifications doc 10679 rev 3 5/11 2 electrical specifications 2.1 thermal data 2.2 absolute maximum ratings 2.3 electrical characteristics t amb = 25c, v s = 5v, unless otherwise specified. table 3. thermal data symbol description value unit r th j-case thermal resistance junc tion-to-case max. 200 c/w table 4. absolute maximum ratings symbol parameter value unit v s supply voltage -0.3 to 7 v t op operating temperature range -40 to 85 c t stg storage temperature -55 to 150 c table 5. electrical characteristics symbol parameter test condition min. typ. max. unit v s supply voltage - 4.5 5 5.5 v i s supply current - - 7.5 12.0 ma filter f c center frequency - 56.6 57 57.4 khz bw 3 db bandwidth - 2.5 3 3.5 khz g gain f = 57 khz 17 20 23 db a attenuation f 4 khz - 22 - db f = 38 khz - 60 - db f = 67 khz - 45 - db r i input impedance of mpx - - 120 - k r l load impedance on filout - 1 - - m s/n signal to noise ratio v in = 3 mv rms 30 40 - db v in mpx input signal f = 19 khz; t3 40 db (1) f = 57 khz (rds) -- 1000 50 mv rms mv rms s rds rds detection sensitivity - 1 - - mvrms
electrical specifications tda7478 6/11 doc 10679 rev 3 s ari ari detection sensitivity - 3 - - mvrms v ref reference - - v s /2 - v demodulator input pins (extres, fsel, tm) all with internal pull down resistor input pin (osel) with internal pull up resistor i pd input current v in = 5 v (pull-down input) 15 - 30 a i pu input current v in = 0 v (pull-up input) -25 - -10 a v ih input voltage high - 0.7 v s 0.8 v s -v vil input voltage low - - 0.2 v s 0.3 v s v output pins (rdcl, rdda, qual, t57) v oh output voltage high i l = 0.5 ma 4 4.6 - v v ol output voltage low i l = 0.5 ma - 0.4 1 v oscillator v cll input level oscin pin osel = open circuit - - 1 v vclh input level oscin pin osel = open circuit 4 - - v amplitude oscout osel = open circuit - 4.5 - v v pp amplitude oscin (for external drive) osel = gnd, f = 4.332 mhz osel = gnd, f = 8.664 mhz - 100 120 - mvpp mvpp 1. the 3 rd harmonic (57 khz) must be less than -40 db with respect to the input signal plus gain. table 5. electrical characteristics (continued) symbol parameter test condition min. typ. max. unit
tda7478 output timing doc 10679 rev 3 7/11 3 output timing the rds (1187.5hz) output clock on rdcl line is synchronized to the incoming data. according to the internal pll lock condition dat a change can result on the falling or on the rising clock edge. (see figure 3 ). whichever clock edge is used by the decoder (rising or falling edge) the data will re main valid for 416.7 s after the clock transition. figure 3. rds timing diagram 2$#, 2$$! ?s td ?s ?s ?s ?s $!4! ,).% #,/#+ ,).% '!0'03
oscillator controls (fsel, osel) tda7478 8/11 doc 10679 rev 3 4 oscillator controls (fsel, osel) two different crystal frequencies can be used. the adaption of the internal clock divider to the external crystal is achieved via the input pin fsel. see the following table for reference. a special mode is introduced to reduce emi. with pin osel connected to gnd the internal oscillator is switched off and an external sinusoidal frequency could be applied on oscin. the peak to peak voltage of this signal can be reduced down to 60 mv. in this mode the fr equency selection via fsel is still active. suggested values of c1 and c2 are shown in the following table. table 6. crystal frequencies crystal fsel (pin configuration) 4.332mhz 8.664mhz connected to gnd or open connected to vs table 7. c1 and c2 suggested value crystal c1 c2 4.332mhz 8.664mhz 27pf 27pf 47pf -
tda7478 package information doc 10679 rev 3 9/11 5 package information in order to meet environmental requirements, st offers these devices in different grades of ecopack ? packages, depending on their level of environmental compliance. ecopack ? specifications, grade definitions and product status are available at: www.st.com . ecopack ? is an st trademark. figure 4. tssop16 mechanical data and package dimensions /54,).%!.$ -%#(!.)#!,$!4! $)- mm inch -). 490 -!8 -). 490 -!8 ! ! ! b c $ % % e , , k ?min ?max aaa .ote $and%doesnotincludemoldflashorprotrusions -old flash or potrusions shall not exceed mm inch perside 433/0 % *edec-/ !" "odymm '!0'03
revision history tda7478 10/11 doc 10679 rev 3 6 revision history table 8. document revision history date revision changes 09-jul-2004 1 initial release. 14-nov-2004 2 add in the ta bl e 5 ?rds and ari detection sensitivity? parameters. 30-jun-2011 3 document reformatted. updated order code in table 1: device summary on page 1 .
tda7478 doc 10679 rev 3 11/11 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 parti cular 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 authorized st representative, st products are not recommended, authorized or warranted for use in milita ry, 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. st products which are not specified as "automotive grade" may only be used in automotive applications at user?s own risk. 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. ? 2011 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 - philippines - singapore - spain - sweden - switzerland - united kingdom - united states of america www.st.com

▲Up To Search▲

Price & Availability of TDA747811

	To Download TDA747811 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .