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This thesis design -oriented chip bonding packaging field frequency ultrasonic generator in wide frequency domain driven gold ball wire bonding transducer , intelligent search optimum operating frequency of the transducer and the dynamic phase-locked to achieve optimum power output of the transducer . Among them , the work carried out and the results are as follows : (1 ) transducer equivalent circuit model and the admittance circle analysis , simulation and experiments, the the transducer resonant modes of the electrical characteristics of its lock phase characteristics , provide a clear signal acquisition scheme for frequency ultrasonic generator and phase locking algorithm theoretical basis . ( 2 ) it excited mode frequency ultrasonic generator overall design of the system and micro- controller system , DDS signal generation system , filtering system , power amplification , signal acquisition systems , signal conditioning , feedback systems , human-computer interaction system , power system studies , programs and detailed circuit design . (3) In order to obtain fast switching , low distortion , high stability and wide spectrum of the signal source , the system introduces communications DDS technology . Flexible, fast conversion speed AVR microcontroller to control the DDS system . Supplemented with anti- transistor thermal breakdown of the high - fidelity Class AB power amplifier circuit and sophisticated design of the filter , the ultrasonic generator sinusoidal signal with excellent output . The same time , based on the true-rms frequency track circuit , the introduction of the true power of the RF field detection chip , it has fast , accurate feedback the complex transducer current signal to the linear and decibel form of DC voltage value to the microcontroller . Microcontroller through the maximum value and the minimum value of the judgment after the analog - to - digital conversion of the digital , respectively, to achieve the transducer series and parallel resonant frequency tracking . Additional voltage and current phase detection circuit , the further strengthening phase locked capability . Finally, the system improve the man-machine interface , USB communication and signal amplitude , workers set time CNC program . (4) The experiments show that the frequency ultrasonic generator has a wide frequency domain - driven , multi- resonant the modal frequency locked , the excellent performance of the digital control , fast phase-locked and impedance analysis .
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