| 摘要 |
A drive circuit ( 18 ) produces a drive signal for a pump ( 10 ) having a piezoelectric actuator ( 14 ), with the piezoelectric actuator ( 14 ) forming a part of the drive circuit ( 18 ) and serving to shape a waveform of the drive signal. The drive circuit ( 18 ) comprises a pulse generator ( 100 ) which generates pulses; a converter circuit ( 102 ) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator ( 14 ). The piezoelectric actuator ( 14 ) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator ( 14 ) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator ( 100 ) comprises a microcontroller-based pulsed width modulator (PWM) circuit ( 116 ) and the converter circuit ( 102 ) comprises a flyback circuit.
|
