The INMP521 is a high performance, ultra-low noise, low power, digital output bottom-ported omnidirectional MEMS microphone. The INMP521 consists of a MEMS microphone element and an impedance converter amplifier, followed by 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 INMP521 is function and pin compatible with the INMP421 microphone, providing an easy upgrade path.

The INMP521 has a very high SNR and common sensitivity of −26 dBFS, making it an excellent choice for far field applications. The INMP521 has an extended wideband frequency response resulting in natural sound with high intelligibility. Low current consumption and a sleep mode with less than 1 µA current consumption enables long battery life for portable applications. The INMP521 complies with the TIA-920 Telecommunications Telephone Terminal Equipment Transmission Requirements for Wideband Digital Wireline Telephones standard. The INMP521 is available in a thin 3 mm × 4 mm × 1 mm surface-mount package. It is reflow solder compatible with no sensitivity degradation. The INMP521 is halide free.

Product Details

Part # Market Status Output Port Location SNR AOP Sensitivity Package Size LF Cutoff
UNITS: dBA dB SPL dbfs (mm) Hz
Production PDM Bottom 65 120 -26 3 x 4 x 1 100

Documentation & Resources


  • Small and Thin 3 mm × 4 mm × 1 mm Surface-Mount Package
  • Omnidirectional Response
  • Very High SNR of 65 dBA
  • Sensitivity of −26 dBFS
  • Extended Frequency Response from 100 Hz to 16 kHz
  • Low Current Consumption: 900 µA
  • Sleep Mode for Extended Battery Life, <1 µA consumption
  • 120 dB Maximum SPL
  • High PSR of -80 dBFS
  • Fourth-Order Σ-Δ Modulator
  • Digital PDM Output
  • Compatible with Sn/Pb and Pb-Free Solder Processes
  • RoHS/WEEE Compliant