Impedance matching circuits may or may not be necessary, depending on the frequency of the device you are driving. Low frequency piezo devices (DC to 100kHz) are often used in non-resonant applications. Additionally, power amplifiers in these ranges are typically not load dependent and are designed for impedance mis-match. The impedance of the piezo device (load) in this case does not dramatically affect the amplifiers performance.
Driving high frequency piezo devices (100 kHz – 20 MHz), on the other hand, requires precise matching of the device impedance to the amplifier output. This can be achieved to an acceptable degree of accuracy using an adjustable impedance matching device or by designing a custom matching circuit.
APC is proud to offer a line of SVR amplifiers for powering actuator devices (DC-1 kHz), RF amplifiers for higher frequency devices (20 kHz – 12MHz @ 100W) and impedance matching boxes to take the mystery out of powering piezo devices. Custom power amplifiers are available through APC by request. APC is currently offering like new-used stock of several High Power LE Amplifier Systems but stock is limited so order soon!!!