Electronic – Sensitivity in an ultrasonic transducer Specification


So far I understand that Sensitivity of the transducer is defined as the ratio of its electrical output to mechanical input.

While going through ultrasonic transducer specs, they have a rated sensitivity e.g. -25db/V/uBar

  1. Can someone please explain the rated sensitivity in simple terms ?
  2. How is this used in calculating amplitude of a receiving transducer (mV), when it receives lets say 10dB ?

Best Answer

The sensitivity of a microphone can certainly be written as so-many dBV/Pa or so-many dBV/uBar so maybe you have one too many "/" in your data sheet.

For instance 0 dBV is precisely 1 V RMS and -25dBV is 56.2mV RMS so this hopefully answers the first part of the formula.

Sound pressure level is usually quoted in dB but when it comes to specifying microphone sensitivities pascals or Bars are used as representative of the RMS pressure.

For instance an SPL of 94 dB is 1 pascal and 1 pascal also equals 0.00001 bar. 1 uBar is therefore 0.1 pascals. Remember these are RMS values of sound pressures.

EDITED above because wrong mV stated for -25dBV