SLAA907D September 2019 – December 2021 PGA450-Q1 , PGA460 , PGA460-Q1 , TDC1000 , TDC1000-Q1 , TDC1011 , TDC1011-Q1 , TUSS4440 , TUSS4470
Sound waves at a frequency of 20 kHz or greater are referred to as ultrasonic because this frequency range is inaudible to humans.