ST took a completely different approach to top-port microphones. The sound inlet is on the top, but ST’s packaging technology allows for mounting the sensor to the bottom side of the lid instead of having to place it on the bottom of the microphone as the competitors do. This results in a small front chamber, providing good high frequency response, and a large back chamber that gives good low frequency response, and good signal-to-noise ratio. The combination of these factors offers high performance in the top-port microphone, better than the competitors. It uses the same basic geometry as ST’s bottom-port microphone, and results in about the same performance. Users find this desirable, particularly in applications where using both a top-port microphone and a bottom-port microphone and need to have the performance of the two microphones matched, necessary for noise cancellation applications and microphone arrays.