Design of Frequency-modulated Ultrasonic Generator in Ultrasonic Bonding Application

Ultrasonic generator for the ultrasonic bond process is the key system in lead bonding packaging equipment,its function is to drive ultrasonic transducer and keep it in resonance status,and its multiple working frequencies is the key application in the future.The traditional ultrasonic generator does not own the PLL function in a wide frequency range.This article constructs a type of frequency-modulated ultrasonic generator which is able to adapt transducers of different characteristic dynamically and has the highlight for general purpose and wide application.Basing on embedded system and applying agility dependable Direct Digital Synthesizer (DDS) and Phase Locked Loop (PLL) feedback scheme,frequency-modulated ultrasonic generator can find every resonant frequency of the transducer and keep frequency automatic tracking.The experimental results show that frequency-modulated ultrasonic generator is able to drive all of lead bonding ultrasonic transducer of different resonant frequency,and reach the design specification of fast and unerring phase locking.