ZHCSHN2B February 2010 – February 2018 LM48580
PRODUCTION DATA.
Piezoelectric elements such as ceramic speakers or piezoelectric haptic actuators are capacitive in nature. Due to their capacitive nature, piezoelectric elements appear as low impedance loads at high frequencies (typically above 5 kHz). A resistor in series with the piezoelectric element is required to ensure the amplifier does not see a short at high frequencies.
The value of the series resistor depends on the capacitance of the element, the frequency content of the output signal, and the desired frequency response. Higher valued resistors minimize power dissipation at high frequencies, but also impacts the frequency response. This configuration is suited for use with haptic actuators, where the majority of the signal content is typically below 2 kHz. Conversely, lower valued resistors maximize frequency response, while increasing power dissipation at high frequency. This configuration is ideal for ceramic speaker applications, where high frequency audio content needs to be reproduced. Resistor values are typically between 10 Ω and 20 Ω.