4 ms·

Not sure that really qualifies as "even better"... "Even better, there is no microphone", is about the only "even better" scenario than the signal lines being

• mlyle 6y ago
  OK, so you'd rather have a big, high gain, low output impedance amplifier enabled and driven with the audio waveform but the signal line gated... than the device unpowered and the signal line connected to ground via the ESD protection path in the package. K. I'd have a decent chance at recovering the audio in the former case, but nil in the latter.. For instance, if it's gated with a FET, and then hooked up to a SOC ADC pin that's multiplexed with other functions, one could use those other functions to provide biasing opening the FET. If it's gated with something better-- e.g. an actual relay-- the audio waveform may still be recoverable: it's very, very large in magnitude compared to how it is with the device unpowered, and will be consuming variable amounts of power with the audio waveform. You might be able to recover the signal by measuring power nets AC coupled with lots of gain.
  • pengaru 6y ago
    I wasn't aware the two were mutually exclusive. Why wouldn't you cut the power AND the signal? That MEMS microphone is producing analog output, is it not? I did a cursory search for the printed part numbers but came up empty handed.
    • mlyle 6y ago
      It looks like an analog part, yes, going to an ADC. Sure, cutting both would be even better. But-- as I posted earlier-- recovering a signal from a depowered MEMS device would be somewhat miraculous. https://news.ycombinator.com/item?id=25743822 https://news.ycombinator.com/item?id=25743822