Low-noise microphone with TDM digital output ideal for speech recognition arrays and more

TDK InvenSense ICS-52000 is a low-noise digital TDM output bottom port microphone in a small 4mm × 3mm × 1mm surface-mount package. It is available now from Mouser. The device consists of a MEMS sensor, signal conditioning, an ADC, decimation and anti-aliasing filters, power management, and an industry standard 24-bit TDM interface. The TDM interface allows an array of up to 16 of the microphones to connect directly to digital processors, such as DSPs and microcontrollers, without the need for an audio codec in the system. All microphones in an array sample their acoustic signals synchronously, enabling precise array processing. The device features a high SNR of 65dBA and a wideband frequency response. The sensitivity tolerance is ±1dB enabling high-performance microphone arrays without the need for system calibration. It has two power states: normal operation, and standby mode. The microphone has a soft unmute feature to prevent pops on power-up. From the time that the device starts to output data, the volume will ramp up to the full-scale output level over 256WS clock cycles. With a 48kHz sampling rate, this unmute sequence will take about 5.3ms.