The ADMP421 is a low cost, low power, digital output bottom ported omnidirectional MEMS microphone. The ADMP421 consists of a MEMS microphone element, an output amplifier, and a fourth-order Σ-Δ modulator. The digital interface allows for the pulse density modulated (PDM) output of two microphones to be time multiplexed on a single data line using a single clock.
The ADMP421 has a high SNR and a high sensitivity, making it an excellent choice for far field applications. The ADMP421 has a flat wideband frequency response resulting in natural sound with high intelligibility. Low current consumption enables long battery life for portable applications. A built-in particle filter provides for high reliability.
The ADMP421 is available in a thin 3 mm × 4 mm × 1 mm surface-mount package. It is reflow solder compatible with no sensitivity degradation