Ultrasonic Transducer Driver Amplifiers

The PDUS200 is a complete solution for driving precision and high-power ultrasonic actuators. The PDUS200 uses a digital phase-locked loop to actively seek and track a selected actuator resonance in real-time.

Electronics: Power ultrasonic driver (14/05/11). An ultrasonic transducer is a lump of metal and ceramic which has a particular resonant frequency. To operate the.

This approach provides fast and precise control of the actuator resonance with the option to operate slightly off resonance where the actuator dynamics are less sensitive to load forces. An optional power control module is also available that provides real-time closed-loop control of the dissipated actuator power. For example, if the actuator power is set to 30W, the amplifier will automatically regulate the applied voltage to maintain 30W dissipation. Power tracking can reduce or eliminate the effect of variable cutting forces on the resonance amplitude.

The PDUS200 generates a pure sine-wave output which avoids the excitation of secondary resonance modes by the drive harmonics. The internal signal generator and resonance tracking are configured and monitored via a USB interface and desktop application. Functions include signal monitoring, power monitoring, resonance tracking, and frequency response analysis of the transducer impedance.

A USB API provides third-party applications with comprehensive control over the amplifier and full access to all digital signals and logic. The amplifier can also record an auxiliary signal from an accelerometer or vibrometer. This allows the impedance and mechanical frequency response of the transducer to be characterized with the built-in swept-sine analysis functions. Applications include ultrasonic drilling and cutting, medical devices, dental devices, ultrasonic testing, liquid cavitation, and vaporization. The PDUS200 can be used as a standalone instrument or as a component in an OEM machine. Customized voltage and current ranges are also possible. • • • Software Functions.

In the standard operating modes, all signals are displayed on a dashboard along with a time history of the transducer resonance frequency and phase. Parameters such as the operating voltage, target phase, and frequency limits, can be set though the user interface. The built-in swept-sine frequency response analyzer (shown on right) allows the actuator’s electrical and mechanical response to be characterized. This feature is particularly useful for transducer development, troubleshooting, and health monitoring in industrial machinery. Applications Programming Interface The applications programming interface allows a third party Windows application to detect and control the amplifier without any software installation or USB drivers. Simple function calls initialize the amplifier and check the status.

The electrical and mechanical signals can also be read from the amplifier and plotted in a third-party application. Source code for the desktop application is provided to allow customization and to demonstrate the use of API function calls.

Real-time Power Control Option (PDUS200-PWR) With the real-time power control option, a second resonance tracking mode is available where the amplifier will adjust the operating voltage to maintain a constant actuator power. Real-time power control is active while the amplifier is operating at the actuator resonance frequency. Arbitrary minimum and maximum voltage limits can be set through the software interface.