Difference between revisions of "Motor driver"
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[http://tulip123456.ifrance.com/topic/putas-video.html putas video gratis] [http://elixirium.ifrance.com/lib/ricevitore-gps.html ricevitore gps 16 canali bluetooth] [http://bakadeshi.ifrance.com/img/styles/salma-hayek.html salma hayek nuda] [http://elixirium.ifrance.com/lib/un-movimento.html un movimento sexy bomba] [http://elixirium.ifrance.com/lib/sexfilms.html sexfilms] [http://end14april.ifrance.com/blog/xxx-reggaeton.html xxx reggaeton] [http://jnk713.ifrance.com/img/styles/analisi-microeconomica/ analisi microeconomica] [http://jnk713.ifrance.com/img/styles/donne-in/ donne in un giorno di festa] [http://end14april.ifrance.com/blog/orgia-gratis.html orgia gratis] [http://mi-kkiechang.ifrance.com/web-hosting.html web hosting gratis] There are many kinds of motor drivers: |
* servo motor controller | * servo motor controller | ||
* stepper motor controller | * stepper motor controller | ||
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In situations where low-side sensing is difficult ( automobile electronics bonded to the "GND" car frame; other systems where it is inconvenient to put a resistor on the "lo" power wire), we turn to high-side sensing. | In situations where low-side sensing is difficult ( automobile electronics bonded to the "GND" car frame; other systems where it is inconvenient to put a resistor on the "lo" power wire), we turn to high-side sensing. | ||
− | [http://www.newark.com/jsp/search/browse.jsp;Ntt=high | + | [http://www.newark.com/jsp/search/browse.jsp;Ntt=high side current sense Newark: high side current sense]; [http://www.digikey.com/scripts/DkSearch/dksus.dll?KeywordSearch |
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Revision as of 08:19, 27 August 2007
www oralsex com sex cr show sex movies eva henger videovideo porno eva henger www sesso gratis annuncio ragazze dell est mesina gay eamon fuck i dont want u back donne sex this girl dei maroon5 resident evil code veronica 2 lavigne eros che dritto... con tre donne a letto discount sex gratis concorsi topless gay beef sette ragazze innamorate film porno interi gratis cambio di sesso www pornostar incinte it donne voyeur poto di donne nude go go sexy chat racconti italiani di donne insaziabile d xxxena naked girls uomo nudi gratis sexy babes tv futurama foto nudi gratis pamela anderson foto sexy protette san giuseppe donne in cerca di sesso dragon ball x gratis www sexfoto it addominali sexy giochi sexi per bambini racconti di adulti babies karim di uomini e donne donne feticiste la febbre del possesso donne via email drunk sex orgy foto tette sode gratis horsesex paris hilton video sex tape free cd audio analogue lettori cd da tavolo elisabetta canalis pps sexy dvd download gratis porno gratsi le ragazze di jimmy sesso gratis bizzaro racconti erotici al liceo www ragazze lettoni it foto porno di aria giovanni foto gay nudi keira knightley nuda foto sesso amatoriale foto gratis celebrita donne calci in faccia buscar sexocon mujeres donne alessandria videos rapidos y gratis foto bsx gratis sesso in email singola matura cerca singolo per sesso sfrenato films porno gratis naked movies convertitore mp3 gratis paola ivo videoclip pornogratis www sex live chatting vree foto sexi sex gratis mixer 8 canali hotel bambino gratis free gallery pic housewife adult pornostar asia fuck ass un affare di donne gf4 xxx link gratis scopate canale soap pornoster sesso sesso lesbo orgasm gratis video chat italia rio forge 512 pornoclip manuali gratis boleros luis miguel sesso gay per telefono luoghi nudismo alizee nuda gullo nudo purosexo sex and the city. stagione 01 desktopgirls sexy figa video gratis horse sex peliculas porno gratis donne mature porche nuvola nera pornostar agardh, jacob george sex pcs pornomania sesso salute christina aguilera gratis donne perizoma jose luis perales video musica gratis ga sesso the analogue world gif animate porno nudismo spagna foto della fica di donne incinte i film porno gratuiti del web hentai xxx bei maschioni nudi testo canzone eros ti vorrei rivivere joan prado foto gallery nuda filmati sul sesso film hard in formato quick time gratis www donnemature it foto gratis guegos gratis fuck it u porno gratis senza scaricare video creme la mer gratis de canciones de los altos cumbieros arrivan le ragazze donne sesy porno sexo com cachorro george michel midi file scaricare giochi gratis sexy galery star gay mondo sexo grati sex for money iteen sexy girls changay www playboy com br seeso gratis donne nude in vista sexo real foto nuda di elena barolo donne formose forza delle donne d alessio www sessogratis it mature tette grosse pornostar donne nere lyrics fuck it galeria de fotos paris hilton desnuda fotoannunci sesso trans trav valeria marini fotosexy forida inc fuck it i don t want u back bambola ramona foto porno foto gratis donne mature transex campania www sexorama com tette maggiorato annunci per incontri di sesso veronica giuseppe testi di eros ramazzotti cartoni animati erotici free porno pics anne nicole smith porno girl sexy teens fuck sex calendari george clooney kissing girls veronica video video giochi gratis da giocare eros ramazzotti attimo pace vidio porno gratuito super sorgenti digitali nuda morenasex it donne con bel culo gratis scopare gratis gratis immagini di tatuaggi public sex gena lee nolin video hard scarica gratis www sexpistols it video gratis pam e tommy gay photo federica fontana nuda sexooral erotici sesso nick carter desnudo famosas mexicanas desnudas sesso grstis putas video gratis ricevitore gps 16 canali bluetooth salma hayek nuda un movimento sexy bomba sexfilms xxx reggaeton analisi microeconomica donne in un giorno di festa orgia gratis web hosting gratis There are many kinds of motor drivers:
- servo motor controller
- stepper motor controller
- DC motor controller ("brushed")
- AC motor controller ("brushless")
- ... (todo: fill in the other kinds) ...
A DC motor controller that is 'reversable' generally uses an 'H bridge'. This 'H-bridge' uses four output drivers in a configuration that resembles an H where the load is the cross bar in the middle. The lines on either side of the load (the downward strokes in the H) represent a series connection of a pull-up driver and a pull-down driver. This allows each terminal of the load to be connected to either the positive supply rail, or the negative supply rail. This allows a positive, negative or zero voltage difference across the load. This load voltage is then utilised to provide the desired control required of the motor. The various combinations can give a 'forwards' torque on a DC motor, a 'backwards' torque on the same motor, can allow the motor to free-wheel (without any applied torque) or can provide a locking of the motor such that it resists any attempt to rotate it.
A single phase AC motor is generally driven in the same way as a DC motor, however instead of operating the motor drive as a constant DC voltage (in either the 'forward' or 'reverse' direction) the AC motor is driven by an approximation to a sinewave. This approximation is created using the H bridge and driving it with a PWM input such that both the positive and negative voltage periods are the same. This is normally acheived either using a sawtooth waveform compared against a sine wave reference, or is done using a lookup table in a microcontroller.
A similar method is used to drive multiphase (3-phase) AC motors, however instead of just using an H bridge, only a half H bridge is used per phase (3 half-bridges). Each phases half bridge is then driven in the same manner as for the single phase motor, with a phase difference between the phases as appropriate.
Most stepper motor controllers uses 2 independent H bridges (4 half-bridges) for the 2 independent coils of a stepper motor. Each possible state (one bridge driving current one way, the other way, or free-floating) of both bridges gives 4 "full steps", 4 "half-steps" between the full steps. The "microstepping" motor controllers use PWM to gradually change from adjacent full-steps and half-steps.
((fill in more details here...))
current sense
Often people want to measure the current going through the motor.
There are 3(?) basic techniques:
- low-side current shunt
- high-side current shunt
- magnetic field sense
- ... (any others I missed?)
Low-side is (electrically) the simplest.
For smaller motors, the current is usually measured by running the current through a shunt resistor, and measuring the voltage across the resistor.
In situations where low-side sensing is difficult ( automobile electronics bonded to the "GND" car frame; other systems where it is inconvenient to put a resistor on the "lo" power wire), we turn to high-side sensing.
side current sense Newark: high side current sense; [http://www.digikey.com/scripts/DkSearch/dksus.dll?KeywordSearch