Œl FE RRANTI ZNA134 Lï:J semiconductors CCIR/EIA TV Synchronising Pulse Generator I FEATURES . . . . . . . . . . 026 and 626 lins standards. CCIRand ElAstandard outputs. SIngle 6 volt aupply. fullv TTLcompatibla. easy synChroniaingbatwaan genarat<l<8. Direct r88et ta vartlcal and horizontal countara. FociIltyfor adding and subtroctlng iines. Automatlc Intarlocing. On chlp osclll.tor (req"lrlng axternal crystal). Canba drivan wlth an external oacillator. Field raference output. . Extondad Temperature Ronge eveilable ZNA134 H RED GENERAL DESCRIPTION ~~~~I~ ~ ~ttY::~~ gC~~I~~~~~~,,"; s~:g ~~ ~::r::=,::!;'~a::~~r t~:~::':~::::'~ ~ 826 or 626 line commercial. Indunrlol or militory telovlaion ayatoms. The aynchronouo divldera and docodlng loglc employad wlthln the unit anaure pertact Interlaci>. together wlth apike"free output woveforma havlng prec'sely 4efined relnlve positions and pulse wldthé: Thedevlceiaçontalned Ina10 pin D.I.L. and can be..lectedtooPMoteoverthe militory tempat8ture range. 'Dopandanl on lino systomusod. sori.. 'osonanl. SYSTEM DIAGRAM 0"'" ",. <""."" "n" "" UN< "'" f'IJ ~ ~ lN ~ ZNA134 CHARACTERISTICS ABSOLUTE MAXIMUM RATINGS Maximum value Pa,ameter Supply Voltege Input Voltage Operating Temperature Range Storage Tempe,ature Range 1 volts 5 volts O'C ta +10'C' -65'Cto+150'C OPERATING CHARACTERISTICS (over recommended temperature ,ange) Parameter Symbol Supply Voltage Vcc Supply Current Is Hi:l:;.-levellnput Va ge Low-Ievellnput Voltage Min. Test conditions 4.15 Typ. 5.0 Max. 5.25 - 100 V,H 2.4 - - V'L - - 0.8 Unit - Volts mA y;;j; Volts . High-Ievellnput Current l'H Vcc = 5V, V, (See Note 1) .; 2.4V - - 40 !'Â Low-Ievel Input l'L Vcc= 5V, V,= OV. (See Note 1) -40 - - !'Â High-IevelOutput Voltage VOH Vcc - 2..4 - - Volts Law-Ievel Output Voltage VOL Vcc = 5V,I,'"k .; 3.2 mA - - 0.5 Volts Clock froquency feloek 625lines, Mode = '1' 525 lines, Mode '0' - - 2.58250 2.5830 - MHz External Oscillator t,. -ve going pulse, 625/525 lines 150 200 Currenl Pulse Width 5V,I...~. ';80~A (See Note 2) (See Note 2) - 260 MHz ns Note 1 Input conditions only apply ID mode, horizontal roseL vertical reseL line sublract and line add, For input conditions of oscillalor Inputs C.0.1, C.0.2, sae epplications seclion, Note 2 Ali outputs - mixad svnc, mixad video blanking, linà drive, reference clock, mixad cathode blanking, even field end field drive have internai 1Oka pull-up resislo". Edoe speeds and sourcing capability cen ho increesad, if requirad, by the addition of e",ernal pull-up resistors. These should heve e minimum value of 2kl1. ZNA134 OUTPUT WAVEFORMS (a) 625 lino CCIR atandard output (Mode = 1). Cryatal frequency 2.5625 MHL Une frequency = 15.525 kHL Field frequency Une period = 64 l'S, Field period = 20 rn.. - _OS.!: 25l- - 50 Hz. ~25l--' , b~~~C~ , , ~~!O-t, ~1>Sl~ c'::~01TTll rTTTT M'>Slfrn-'" -~ I:II~IIII : , : : ":l:'- ~>5r= Flold d,Ive: U I , l-O' IIII~III, :: :2'5l:>5l,2~l, O! U >56.~:' tfrmf ,~"'~~ :': MI..d ":'\;~i ~--------- ~"'FloldIE"'1 l56.~1, 31>5l IIn"lmo - i . :~ : . "~~:::"""'6'.. Jl 20d Flold 10ddi ..<i-2-29.. : """""0 poon' : : ID".HI '~'.'.;..i 229..~ ~ i-.I- 0:5l :',0 : : ~ ,' ~~~ ~I~~~ : : inffi , :L U lI1mIlliII1flr "0'pulm ~ ; ".'.. ,: !>Sl:2'5l,m, MI..d , ' H>5'f : l"'..->/ -i ;""..,.. : : ZNA134 (b) 525line ElA standard output (Mode Crystal frequency = 2.5830 MHz Une frequency - 0). - 15.750 kHz. Field frequency , 6.66 ml. 60 Hz lino period = 63.5 l'S. Field perlod - "":L!::JL=;---2ML---~ ML--::::-,;:::;--2~5L-: b~$1~~uumTll \'00 n-°--lJl , 0 :"1>5L- ~~ra; °l1TlLJITf , --.: >L , s,"'- pu"" 3L , 3L ___m TI8nfIT ' 3L : 3L ' ; ~ --0244L -_oo Lin""""; : mmmmrnmmmr 111111111 ' :. ...; 3L '; "'...n,, point rt: : ,, Ou :' Oi"Li --~o_ou--o_-rTTTi-n-r-° d.'.. -1 ,, L-;.J : - :; : -15OL o~"'LT-j --- , : -lf ml1llLJllT """""'-"""'",,' Li... ---'00: ;'13-5L~, 0 ~ 3L Mi"'-- - - --- 'O244L~ n--r-'ML~ ";ok! d.'., -"'L~35"'--: F 1111:111 1 U : U ,om ! 0244L M".a S"" pulm r ~R : ---~JJ L-i. ; 2ndFi"d(O~dl' : """ilU~C1JL"::"'O37L":ML:'-~:"O244L 1:0 - '- 'om "::'-om r -om- ~ ZNA134 Unes are addad to tha second generator if EF2 is le.. than one field period delayed from Hf, and subtractad il EF2 is greater thon one field psriod delayed trom EFI to raduce synchronisatioh time The add/sublract circuitry con be built using nine TTL packages :4 off ZN7402 1 off ZN7427 1 off ZN7404 1 off ZN74123 1 off ZN74121 1 off ZN7493 The circuit in Fig, 6 adds or sublracts one line PSI trame but this could be extendad to two or more lines psr Irame by adding lunher bits to the 3 bit counter and decoding the relevant states, Similarly hall aline psr frame con be added by decoding 'OC' instead of 'OB', The circuit operates in 625 or 525 line mode without any changes to the compone,,! ".Iues, PACKAGE OUTLINE ZN134H ~ê_~~ ~.LI,,u, , ZNA134 ~7Nff 231 SYNCHRONISATION USING THE UNE AOD/SUBTRACT FACIUTY . Thia ia auitable where generator look muat be achievad gradually, i.e. without loss of picture 1111IIe . receiver, aa in studio camera systems. Line Synchronisation con be achievad smoothly by the use of a pha..lookad loop technique ralher thon the direct Horizontal ReseUechnique (Flg. 5). C.0.2 LO.! . H2 MVB2 FO2 RC2 LO2 5YNC. DEN. 1 1 1 J J r yEF1 t 5220 Fig. 5 Line Lock Circuitry Field Synchronisation (Fig. 6). The generator wavelorms ara brought into synchronisation by adding or subtracting oneline per frame to the second generator until the wavelorms are exactly ln phase. This ia achieved by adding or inhiblting pulses at the start 01 the first fuilline aftor field blenking, thus provonting any changes to the mixed sync. waveform during the broad end equalialng pulse periods. Unes or, '.ddad' by clocking the vertical counter lester than !ha normal haff line rate. Setting line Add high for a periOd equal to 4 Reference Clook pulses, incrementsthevertical countar by one line thus effectlvely raducing the field periOd by one Hne. Unes ara 'subtractad' by inhibiting the clock pul..s to the vertical counter. Setting Line Subtrect high for a perlOd of one lino lesves the state of the vertical counter unchengad for one Ii.. thus effectively incraUing the field period by one lino. Hence the add or subtract periOds ara generatad DYcouqling Reference Clock or Lino Drive pulses respectively with a 3 bit counter. Lines ere addad or subtrectad until the generators ere in phase. The two Even Field outpots togather generate .. pulse.which inhibits the add/aubtrect oircuitry whon an in-phasé condition OCturs. v" 5kA m Fig. 6 Field Lock Circuitry 'A2 '.~2