Acoustic Transfer Assist (ATA) systems are used in media printing devices
to help transfer toner to paper by use of ultrasonic vibrations. The
transducer is driven at its resonant frequency, though somewhat dampened.
To shorten the decay time of the transducer when its vibration is not
desired, a compensating signal is used. A reverse drive voltage is used
during transducer shut-off. The reverse drive causes the transducer to
vibrate at its normal resonant frequency, but at a 180.degree. phase
shift, causing the transducer to stop vibrating significantly faster than
without a reverse drive. An open phase-locked loop system drives the
transducer from resonance to rest. When the transducer stops vibrating,
current to the reverse drive loop is cut off.