Oscillator

From OpenCircuits
(Difference between revisions)
Jump to: navigation, search
m (Reverted edit of 195.251.253.108, changed back to last version by DavidCary)
Line 1: Line 1:
The vast majority of electronic systems operate at some fixed frequency.
+
[http://mrsrl.stanford.edu/seminar/detailview.php?event_id=269 free mp3 ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=273 free nextel ringtones] [http://climate.msrc.sunysb.edu/1984/messages/288.html cheap adipex] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=311 cheap xanax] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,41 sagem ringtones] [http://climate.msrc.sunysb.edu/1984/messages/302.html diazepam online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=244 clonazepam online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,39 polyphonic ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=45 cheap carisoprodol] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=309 wellbutrin online] [http://climate.msrc.sunysb.edu/1984/messages/313.html kyocera ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-225502801748.html ativan online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=73 viagra online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,27 buy lorazepam] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=48 cheap ultram] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=30 free kyocera ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,10 alprazolam online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=234 free alltel ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=57 cheap ambien] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=74 vicodin online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,30 motorola ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=62 free sony ericsson ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=53 free punk ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=51 viagra online] [http://www.bc.edu/apps/bookstore/cards/jun7-224422412742.html phentermine] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=46 xanax online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=70 buy ultram] [http://www.bc.edu/apps/bookstore/cards/jun7-224362564176.html cheap valium] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,17 cingular ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,8 adipex online] [http://climate.msrc.sunysb.edu/1984/messages/301.html cheap cyclobenzaprine] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=51 cheap propecia] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=298 cheap tenuate] [http://www.bc.edu/apps/bookstore/cards/jun7-224512777320.html cheap carisoprodol] [http://climate.msrc.sunysb.edu/1984/messages/353.html ultracet online] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=72 cheap pharmacy online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=76 wwe ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=18 diazepam online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=312 xenical online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=45 free nokia ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=285 qwest ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=79 zanaflex online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=247 diazepam online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=305 verizon ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-226682379944.html motorola ringtones] [http://climate.msrc.sunysb.edu/1984/messages/318.html cheap lortab] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=62 prozac online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=21 free ericsson ringtones] [http://climate.msrc.sunysb.edu/1984/messages/330.html but ortho] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,19 cyclobenzaprine online] [http://climate.msrc.sunysb.edu/1984/messages/295.html celexa online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=253 free free ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=49 phentermine online] [http://climate.msrc.sunysb.edu/1984/messages/300.html free cool ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=52 cheap prozac] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,44 free qwest ringtones] [http://climate.msrc.sunysb.edu/1984/messages/296.html cialis online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=297 sprint ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=60 cheap nexium] [http://climate.msrc.sunysb.edu/1984/messages/339.html free real ringtones] [http://climate.msrc.sunysb.edu/1984/messages/341.html sagem ringtones] [http://climate.msrc.sunysb.edu/1984/messages/351.html tracfone ringtones] [http://climate.msrc.sunysb.edu/1984/messages/328.html nokia ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=284 free punk ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-226172687200.html mp3 ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=295 sony ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,12 buy ativan] [http://climate.msrc.sunysb.edu/1984/messages/309.html but hgh] [http://climate.msrc.sunysb.edu/1984/messages/320.html midi ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=7 free alltel ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=23 flexeril online] [http://climate.msrc.sunysb.edu/1984/messages/346.html free sony ericsson ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=39 motorola ringtones] [http://climate.msrc.sunysb.edu/1984/messages/359.html vicodin online] [http://www.bc.edu/apps/bookstore/cards/jun7-226062830562.html free tracfone ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=42 soma online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=260 order levitra] [http://climate.msrc.sunysb.edu/1984/messages/322.html motorola ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=19 didrex online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=84 cheap sildenafil] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=48 pharmacy online online] [http://climate.msrc.sunysb.edu/1984/messages/366.html cheap zoloft] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=257 cheap hydrocodone] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=63 free sony ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=82 free cingular ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=306 viagra online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=47 buy paxil] [http://climate.msrc.sunysb.edu/1984/messages/292.html ambien online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=264 lortab online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=28 hydrocodone online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=85 vigrx online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=10 ativan online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=26 hgh online] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=63 sildenafil online] [http://climate.msrc.sunysb.edu/1984/messages/358.html buy viagra] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=71 ortho online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=44 nextel ringtones] [http://climate.msrc.sunysb.edu/1984/messages/316.html lisinopril online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,24 free funny ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,46 sony ericsson ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=307 vicodin online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,25 hydrocodone] [http://climate.msrc.sunysb.edu/1984/messages/293.html ativan online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=38 mono ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,18 clonazepam] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=31 online levitra] [http://climate.msrc.sunysb.edu/1984/messages/349.html free sprint ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=49 cheap cialis] [http://climate.msrc.sunysb.edu/1984/messages/347.html free sony ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,26 order levitra] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=313 cheap zanaflex] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=44 but phentermine] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=12 celexa online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=69 ultracet online] [http://climate.msrc.sunysb.edu/1984/messages/362.html wwe ringtones] [http://climate.msrc.sunysb.edu/1984/messages/343.html sharp ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,36 norco online] [http://climate.msrc.sunysb.edu/1984/messages/345.html soma online] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=61 ultracet online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=242 cingular ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=232 cheap adipex] [http://climate.msrc.sunysb.edu/1984/messages/364.html cheap xenical] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=6 cheap albuterol] [http://climate.msrc.sunysb.edu/1984/messages/350.html tenuate online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=83 cheap ortho] [http://climate.msrc.sunysb.edu/1984/messages/325.html free music ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=288 free sagem ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=262 cheap lisinopril] [http://climate.msrc.sunysb.edu/1984/messages/319.html cheap meridia] [http://climate.msrc.sunysb.edu/1984/messages/335.html cheap propecia] [http://climate.msrc.sunysb.edu/1984/messages/360.html order vigrx] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=20 cheap diethylpropion] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=233 cheap albuterol] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=40 free mp3 ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=265 cheap meridia] [http://climate.msrc.sunysb.edu/1984/messages/307.html free free ringtones] [http://climate.msrc.sunysb.edu/1984/messages/354.html cheap ultram] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=61 cheap soma] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=35 cheap lortab] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=292 cheap sildenafil] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,34 nextel ringtones] [http://climate.msrc.sunysb.edu/1984/messages/317.html lorazepam online] [http://climate.msrc.sunysb.edu/1984/messages/308.html free funny ringtones] [http://climate.msrc.sunysb.edu/1984/messages/368.html buy diethylpropion] [http://www.bc.edu/apps/bookstore/cards/jun7-226002359520.html free ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=76 free funny ringtones] [http://climate.msrc.sunysb.edu/1984/messages/297.html free cingular ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-224302380012.html soma online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=274 nokia ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=55 cheap clonazepam] [http://climate.msrc.sunysb.edu/1984/messages/367.html zyban online] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=64 clomid online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=283 prozac online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,53 valium] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=33 cheap lisinopril] [http://www.bc.edu/apps/bookstore/cards/jun7-225692379850.html meridia online] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=41 tramadol online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=60 sharp ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=266 free midi ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=252 flexeril online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=55 free real ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=240 celexa online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=314 zoloft online] [http://climate.msrc.sunysb.edu/1984/messages/327.html nextel ringtones] [http://climate.msrc.sunysb.edu/1984/messages/304.html free ericsson ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,32 music ringtones] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=41 free mtv ringtones] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,52 ultram online] [http://climate.msrc.sunysb.edu/1984/messages/356.html valium online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,55 order viagra] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=58 cheap lorazepam] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=13 cheap cialis] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,38 cheap phentermine] [http://climate.msrc.sunysb.edu/1984/messages/326.html nexium online] [http://www.bc.edu/apps/bookstore/cards/jun7-226732674842.html free samsung ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-225822801712.html cheap norco] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=52 meridia online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,48 free sprint ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=74 rivotril online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,15 cheap carisoprodol] [http://climate.msrc.sunysb.edu/1984/messages/294.html carisoprodol online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=246 buy cyclobenzaprine] [http://climate.msrc.sunysb.edu/1984/messages/369.html free qwest ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-226472592872.html qwest ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=47 fioricet online] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=72 verizon ringtones] [http://climate.msrc.sunysb.edu/1984/messages/337.html free punk ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=256 cheap hoodia] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=279 cheap pharmacy online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=300 free tracfone ringtones] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=301 tramadol online] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=287 cheap rivotril] [http://ocw201-1.usc.edu/iPIDD/ju_board/view.php?message_ID=68 tramadol online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,21 didrex online] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,22 cheap fioricet] [http://mrsrl.stanford.edu/seminar/detailview.php?event_id=271 music ringtones] [http://groups.ku.edu/cgi-bin/cgiwrap/kuksa/forum/ezboard.cgi?db=general&action=read&dbf=65 cheap albuterol] [http://brown.cla.sc.edu/projects/pas/bforum/index.php?method=showhtmllist&list=message&rollid=2,35 free nokia ringtones] [http://www.bc.edu/apps/bookstore/cards/jun7-225582064618.html viagra online] [http://climate.msrc.sunysb.edu/1984/messages/291.html alprazolam online] The vast majority of electronic systems operate at some fixed frequency.
  
 
Usually the component that fixes that frequency is a crystal made of silicon, sealed in a metal can.
 
Usually the component that fixes that frequency is a crystal made of silicon, sealed in a metal can.
Line 30: Line 30:
 
* [http://techref.massmind.org/techref/clocks.htm massmind: clocks]
 
* [http://techref.massmind.org/techref/clocks.htm massmind: clocks]
 
* [http://en.wikipedia.org/wiki/Crystal_oscillator Wikipedia: crystal oscillator]
 
* [http://en.wikipedia.org/wiki/Crystal_oscillator Wikipedia: crystal oscillator]
* [http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en021190 "App Note AN949: Making Your Oscillator Work" by Brett Duane]
+
* [http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE
* [http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en020706 "App Note AN943: Practical PICmicro® Oscillator Analysis and Design" by Ruan Lourens]
+

Revision as of 15:16, 14 June 2007

free mp3 ringtones free nextel ringtones cheap adipex cheap xanax sagem ringtones diazepam online clonazepam online polyphonic ringtones cheap carisoprodol wellbutrin online kyocera ringtones ativan online viagra online buy lorazepam cheap ultram free kyocera ringtones alprazolam online free alltel ringtones cheap ambien vicodin online motorola ringtones free sony ericsson ringtones free punk ringtones viagra online phentermine xanax online buy ultram cheap valium cingular ringtones adipex online cheap cyclobenzaprine cheap propecia cheap tenuate cheap carisoprodol ultracet online cheap pharmacy online wwe ringtones diazepam online xenical online free nokia ringtones qwest ringtones zanaflex online diazepam online verizon ringtones motorola ringtones cheap lortab prozac online free ericsson ringtones but ortho cyclobenzaprine online celexa online free free ringtones phentermine online free cool ringtones cheap prozac free qwest ringtones cialis online sprint ringtones cheap nexium free real ringtones sagem ringtones tracfone ringtones nokia ringtones free punk ringtones mp3 ringtones sony ringtones buy ativan but hgh midi ringtones free alltel ringtones flexeril online free sony ericsson ringtones motorola ringtones vicodin online free tracfone ringtones soma online order levitra motorola ringtones didrex online cheap sildenafil pharmacy online online cheap zoloft cheap hydrocodone free sony ringtones free cingular ringtones viagra online buy paxil ambien online lortab online hydrocodone online vigrx online ativan online hgh online sildenafil online buy viagra ortho online nextel ringtones lisinopril online free funny ringtones sony ericsson ringtones vicodin online hydrocodone ativan online mono ringtones clonazepam online levitra free sprint ringtones cheap cialis free sony ringtones order levitra cheap zanaflex but phentermine celexa online ultracet online wwe ringtones sharp ringtones norco online soma online ultracet online cingular ringtones cheap adipex cheap xenical cheap albuterol tenuate online cheap ortho free music ringtones free sagem ringtones cheap lisinopril cheap meridia cheap propecia order vigrx cheap diethylpropion cheap albuterol free mp3 ringtones cheap meridia free free ringtones cheap ultram cheap soma cheap lortab cheap sildenafil nextel ringtones lorazepam online free funny ringtones buy diethylpropion free ringtones free funny ringtones free cingular ringtones soma online nokia ringtones cheap clonazepam zyban online clomid online prozac online valium cheap lisinopril meridia online tramadol online sharp ringtones free midi ringtones flexeril online free real ringtones celexa online zoloft online nextel ringtones free ericsson ringtones music ringtones free mtv ringtones ultram online valium online order viagra cheap lorazepam cheap cialis cheap phentermine nexium online free samsung ringtones cheap norco meridia online free sprint ringtones rivotril online cheap carisoprodol carisoprodol online buy cyclobenzaprine free qwest ringtones qwest ringtones fioricet online verizon ringtones free punk ringtones cheap hoodia cheap pharmacy online free tracfone ringtones tramadol online cheap rivotril tramadol online didrex online cheap fioricet music ringtones cheap albuterol free nokia ringtones viagra online alprazolam online The vast majority of electronic systems operate at some fixed frequency.

Usually the component that fixes that frequency is a crystal made of silicon, sealed in a metal can. (Some very-low-cost devices might use a "resonator" or a resistor and a capacitor to fix the frequency).

The entire circuit that generates the frequency is called an "oscillator". (An oscillator that uses a resistor and a capacitor to fix the frequency is called a "RC oscillator". An oscillator that uses a crystal to fix the frequency is called a "crystal oscillator".)

The oscillator includes, in addition to the frequency-fixing component just mentioned, an amplifier and capacitors.

One can buy an "oscillator" in a metal can. Typically an oscillator can has 4 pins. Inside the can is all the components of the oscillator. One applies DC power on 2 of the pins, and the oscillating signal (the "CLK OUT") appears on another pin. (The remaining pin is unused).

Other times one buys just the crystal in a (2-pin) metal can and attaches the other components to build an oscillator.

In either case, the frequency is printed on the top of the metal can.

Many microcontrollers have 2 pins (typically labeled "XTAL1" and "XTAL2", or "OSC1" and "OSC2", or something similar) that are designed to be directly connected to the 2 pins of a crystal. (Capacitors from those pins to VCC and GND are also part of the recommended circuit). An inverter inside the microcontroller acts as the amplifier, and the crystal and capacitors make up the rest of the oscillator.

In systems with multiple CPUs, it is often simpler, cheaper, and more reliable (avoiding metastability problems) to use a single crystal (rather than a dedicated crystal for each CPU). CPUs (and many other components) often have a single "CLK" pin designed to be connected to the wire used to send that "clock signal" (a fixed frequency) everywhere.

Unfortunately, many people confuse the "clock signal" generated by an oscillator (a simple metronome beat, tone, at constant frequency) with far more complicated "clock system"s that keep track of seconds, minutes, hours, and sometimes days, weeks, months, and years.

for further reading

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox