SmartSound™ MEMS Microphones

We're developing a product using ICS-40720 but we're having a problem with our prototype boards: there seems to be a quite strong noise at 2Hz in some microphones. What could be causing this?

I've captured background office noise and I attach 3 screenshots showing the frequency responses of different microphones capturing sound at the same time.

Hello,

I am trying to use ICS-40619 analog MEMS microphones in a demo rig. We have soldered the microphone to a wire (see 1st attachment).

On the other side of this cable, we connected a 3V power supply and a BNC connector (see 2nd attachment). At the power supply, we connected a 0,1 muF capacotor. At the output side we connected 1 muF capacitors.

Hi,

We are using ICS52000 in daisy chain mode for receiving Microphone audio data. We have connected 12 Microphones.

We have configured clocks as WS – 16KHz & Bclk as 512Fs(8Mhz). Though we use 12 Mics, we will receive data in 16 slots. We expected the data in the last 4 slots to be null. But we receive the same data in the remaining slots also, ie in all 16 slots we receive same data.

Can you please explain why are we receiving data in last 4 slots of 16 when 12 MICS are connected.

Expecting your early reply.

Dear All,

The project is for acquiring heart sound device with MCU ADC. The input frequency range are from 20Hz to 2KHz.

For lower frequency performance, a high SPL analog microphone is selected. We also saw some documents about microphone preamp circuit from InvenSense. And AD8605 is used as preamp. The schematic check the followings.

So there are some questions, please give me some comments. Many thanks.

MCU and Analog Power supply is 3.0 V.

ICS-40300 Product SPEC v1.0 design considerations:

1, Dynamic range: MUST add 9db gain (about x2.8);

I am trying to interface the INMP441 with Android based i.mx6 board.

for that i was wondering if invensense have any linux supported device driver available for INMP441 or am i supposed to use the generic i2s driver.

Thanks,
Chandresh

Is there any place I can get a copy of the BOM for the ICS-52000 TDM Array featured in AN-000094?

We are using ICS52000 in daisy chain mode for Microphone audio data receive.

We have configured clocks as WS - 16KHz & 512Fs - Bclk (using 12 microphones).

When BCLK & WS is given to the board, by default , we receive some data. When we play the data it looks very noisy.
When we speak to the Microphone, this noise is also added to the voice data.

We are not clear on whether this is expected .

Kindly let us know whether any additional handling required to avoid the noise in the data.

Hi,

I’m working on the microphone INMP441 on mono-output mode. I see in the datasheet that if the L/R PIN (4) is on low then the left channel is activated, and otherwise the right channel. In my case it’s on low so I expect to have values only in the left channel, which according to the datasheet is in the first 32 bits of every 64-bit sample. Problem is looks like this is not consistent. For example here’s a snapshot from a buffer I get after DMA sampling:

uint16_t data[1024];

I am looking for register maps for ICS-43434 and ICS-52000

The register maps section of this site https://www.invensense.com/download-pdfs/ points to the DataSheet and the data sheet does not have the register map.

Thanks.

Hello,

This documents a method for sealing MEMS microphones from dust and liquid:
https://www.invensense.com/wp-content/uploads/2015/02/Recommendations-for-Sealing-InvenSense-Bottom-Port1.pdf

Are there images, part #'s, and examples we can reference for this protective membrane? Please provide more information, so we can include in our product design.

Thank you,
Aaron