Abstract:
An ultrasonic generator for providing power to a bonding apparatus having a bonding horn which is brought into contact with respective conductive pads and which carries a wire to be dispensed for interconnection therebetween includes a circuit for applying a voltage at an ultrasonic frequency to the bonding horn to produce a bonding current in the horn, and a monitor for monitoring the bonding current applied to the bonding horn. A circuit is provided for maintaining a zero phase difference between the applied voltage and the monitored current. In addition, a circuit is provided for continuously monitoring and controlling the current which is delivered to the bonding horn to produce a current waveform of a predetermined controllable pattern.
Abstract:
A power supply generated through a set of current transformers is disclosed. The current transformers may be removably attached to a primary power line such as a high voltage power line. The power supply may be used to power a device or charge a battery for a device that requires a low voltage input. The power supply may be used in underground vaults and pad mounted chambers that contain high voltage power lines. The power supply may generate a low voltage direct current out put that is not available in the vicinity of high voltage power lines in an underground vault or pad mounted chamber.
Abstract:
A monitor for optimizing the ultrasonic bonding of materials by analyzing the impedance of an ultrasonic transducer used to effect the bond. The electrical impedance of the transducer, which is proportional to its mechanical impedance, is determined by applying an ultrasonic voltage thereto and monitoring the resultant change in current amplitude. A pair of differentiators produces a second derivative signal of the impedance with respect to time, with a negative-going zero crossing of this signal corresponding to completion of the bond. Loss of wire, mechanical malfunctions and improper bonds are also detected by the monitor, to form a real time quality control system.