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[MMA8452Q] - HF disturbances & Interrupts

Question asked by Simon THIEBAUT on Mar 28, 2014
Latest reply on Apr 10, 2014 by Simon THIEBAUT

Hello everybody,

 

We are developing an application using a MMA845Q for waking up the whole system through transient detection interrupts.

Our application also embeds a GSM chip for communication.

 

The fact is the GSM creates HF disturbances of 900 MHz that propagates everywhere in the circuit.

We followed RF design guidelines for the GSM, and also design guidelines for the accelerometer layout + decoupling.

 

However, we got a strange behavior happening very rarely, but that is problematic: it appears that the HF disturbance makes the chip generating a false transient interrupt (no real motion at all).

 

Here are my questions:

Is there any chance that these HF disturbances can disturb the sensor behavior ?

Does anybody already encounter that ?

How can we become robust against that problem ?

 

 

Thank you very much for your help.

 

Have a nice day,

 

Simon

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