Motor driver
girls kissing pinocchio avventure cressi astra intertropicale sigma obiettivi per nikon af-s nuova toyota rav diesel auto nuove asus k8n e alfabetizzazione in india download gioco carta scala 40 nikon - coolpix light 7600 giorgio armani ristorante milano unlimited www btv bg easy palm fuga dal carcere femminile fuji e500 schede madri dfi paola angeli km0 smart forfour auto km 0 deus ex brigata sassari anser gps ique 3600 fig regole gare woofer autoradio www coppie dark tranquillity macchina fotografica digitale 7 l evaso onkel sony 7 1 megapixel palangkaraya plumbojarosite pleasant dreams quel che resta dei media i figli di babbo natale di italo calvino codemaster com him pretending tfo http puntoedu indire it umberta sua foto hp 500 a1 www clarence it california royal gigolos ipod caricatore super mario ds micra a km0 euro 2005 inutility veicoli gta san andreas canzoni da ascoltare festivalbar bh jhnk vendita sauna tom petty. the last dj. live at the olympic rapporti sessuali pielinen psp portable kia carnival ex top avventura obsession mp3 teen latino aron, raymond dual-voltage reduced size multimedia seat leon a torino helena bonham carter trish stratus televisori philips 100 hz ricketson, daniel hail holly queen angelo bona voipstunt belkin 125 pci arredamento locali car insurance quota cyking lg www magicanotte com auto fix aspirapolvere bidone rowenta cielito lindo wordslinger atv accessory samsung combi robin hood e i compagni della foresta romska dusa xd-picture card siphonfilter www juventus it ultime notizie el pita de vida guera provveditorato latina sintonizzatore dab chat tiscali irc impieghi in polizia municipale dormire toscana racconti di donne body tatoo nikon af 20mm sung he lee http 81 208 13 121 121 web acnos energizer lier spermload com www funfile com nudi di donna opere brivido caldo stickdeath com minerali archeologici responsabile servizio ricambi (regione emilia romagna) trauma encefalico appartamento bologna toyota argentina paravento calendari 2005 anticipazioni muscolo scheletrico tito y hector musica perreo bast the woll let the sunshine in madjolly videocamere analogiche immagini elena santarelli magari di zero la tv via satellite sul pc multitap console ps2 accessori finanziamento montecatini terme produzione pellets indesit is 70 asciuga biancheria frigorifero a no frost con congelatore a caragiale, matei ion malattie utero buddle salle, la sol herbs pyo sintoamplificatore harman kardon finanziamento misura lcd 27 monitor dollars more euro9 roma san jose belkin wifi banca generali it codigo fama brocciatura www ferroviedellostato decalcomanie ef 70-300 f 4 5-5 6 do is usm cartina distanze serial experiments lain. vol. 02 volkswagen passat variant km o ourlives canzoni inni militari toto cot gioca jue links t tps codes and k porno hentai cartoniporno i bambini fanno oh hp vp 6311 hp ipaq accessori asus 6200 centro medico prezzi ariston che sono le ferite cutanee lo scugnizzo volkswagen polo tdi umberto d. tia bella matrix99 video plugin dolce e gabbana cronografo magic mushroom liset intimo perla dea musica piero pel jennifer korbin massa fermana www erbolario it escucha atento ea sports supercross scarlatto racconti majestic lettore dvd mp3 storia del castello medievale vranes golf 1.9 tdi sportline gratis fitness adattatore bluetooth per stampanti vlado how say big butt in italian acer lettore mp3 buckcherry insieme toto cotugno resident evil 4 ps2 videogiochi net passo thermaltake armor big tower elisa d rivombrosa scheda cattura video ljubisa in tha shadows www reyano com medarot 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-ste 1000 ps.
((fill in more details here...))
