MP34DTx MEMS Audio Microphones STMicroelectronics MP34DTx MEMS Audio Microphones are compact, low-power, omnidirectional microphone built with a low-profile sensing element. These sensing elements are capable of detecting acoustic waves and are manufactured using a specialized silicon micromachining process dedicated to producing audio sensors. The IC interface is manufactured using a CMOS process that allows designing a dedicated circuit able to provide a digital signal externally in PDM format.