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ADXL355 & ADXL357 Intermittent output on 1 or all channels

Question asked by AndrewC on Apr 20, 2018

I am having intermittent issues with both the ADXL355 and ADXL357 accelerometers (we use them interchangeably due to stock issues). The issues manifest as one of three problems:

  1. All three outputs sit at zero
  2. One output sits at zero
  3. All three outputs have large bias errors (> 1 g).

The issues are usually resolved by power cycling, although sometimes it takes several cycles.

 

So far, I have seen problems 2 and 3 on a single accelerometer (different accs though). Problem 1 has been observed on two devices, one ADXL355 and one ADXL357.

 

I am unable to recreate any of the issues, and have tried the following to do so:

  1. Repeat power cycling 30 and 90 seconds apart (thousands of cycles)
  2. Varying the input voltage and start  up times for our system
  3. Changing the configuration messages I send (our standard is: 125 Hz Data Rate, Internal Sync, +/-2 g range, Measurement Mode). Obviously removing the measurement mode config stops the sensor outputting data, but the others have no effect on the problem.

 

The second problem is the same as the issue here: ADXL355 output stuck at zero . I added a reply to that but got no response. 

 

My setup is the ADXL355/7 on a SPI bus with 2 other devices (another MEMS inertial sensor and an ADC). The ADXL355/7 is powered from 3.3 V and uses the internal LDO regulators.

 

A few questions:

  1. Are there any requirements in terms of power-up, e.g. rise times, etc?
  2. Can you suggest a cause for these issues?
  3. Can you suggest a way of forcing them to happen? 
  4. Can you tell me if any of these are known issues with the device(s)?

 

The performance of these accelerometers is spectacularly good, but if they have a latent problem causing intermittent faults, I think we will have to design them out of our system, as we need high, (and more importantly) predictable reliability.

 

Thank you in advance for any help you can offer.

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