The frequency response of one of ST’s competitors’ bottom-port digital MEMS microphones is shown on this slide. One thing to notice about the competitors’ microphones is the frequency response is specified between 100Hz and 10kHz. This is partially because users initially were only concerned about use in voice applications. Another part of it is because the performance below 100Hz and above 10kHz is not as good. Below 100Hz it drops off quickly and above 10kHz it rises rapidly, but it is relatively flat in the specified range, down about 2dB at 100Hz and up about 1dB at 10kHz.