Vesper of Massachusetts is claiming high fidelity for a MEMs piezo microphone that picks up the vibration of the user’s voice through the skull.
Inside are the mems, an amplifier, and a power regulator.
Called VA1200, the company describes it as
“the world’s first analogue piezoelectric voice accelerometer. Unlike a traditional microphone, the VA1200 is completely immune to ambient sounds, and only picks up the user’s voice. It filters out background noises such as wind noise, music, subway noise and crowd noise.”
- Nominal supply voltage is 1.8V (1.6 – 3.6V) and it typically consumes 160μA.
- Power supply rejection is -91dBA (217Hz, 100mVp-p squarewave, 100 – 2,400Hz A-weighted).
- Output impedance is 400Ω and output offset is 800mV.
- Operation is over -40 to +85°C
It comes in a reflow-compatible 2.9 x 2.8 x 0.9mm package, and applications are foreseen in in-ear hearable products. “Existing earbuds rely on mic arrays and algorithms to suppress environmental noise during voice calls,” claimed marketing director Roberto Condorelli.
VR and AR headsets, as well as smart-frames and smart-glasses are other potential applications.
Vesper also makes more conventional piezo mems microphones, except using broad cantilevers instead of membranes, arguing that these are less likely to clog with dirt and water.