AnsweredAssumed Answered

ADXL375 reaching 200g with small tap

Question asked by Tsibin on Jun 20, 2018
Latest reply on Jun 22, 2018 by jwang

Hello Everyone,

 

I am using ADXL375 sensor for the first time. I am using SPI at 2 MHz with sensor ODR = 3200 Hz. The settings I am using is as follows. 

 

0x2C -> 0x0F

0x38 -> 0x90

0x2F -> 0xF9

0x2E -> 0x00

0x31 -> 0x0B

0x2D -> 0x08

 

I am enabling FIFO and reading the FIFO status before reading the data. I am doing multiple byte read for the reading raw datas. During my tests I am getting values between 4095 and -4096. But even with a small tap (with pencil) on the sensor PCB, I am getting around 200g on one axis (4090 raw counts on z axis). Is this expected ?

 

If I drop the sensor board from 2 cm above the table, I am getting max counts on z axis. I am assuming that 200g is a large force so I am confused when my sensor is reading 200g with the above tests.

 

My self test results are as follows.

Xst = 1.7g

Yst = -1.8g

Zst = 6.1g

 

Is there anything wronge with the settings or the sensor, or am i doing anything wronge? Any suggestion would be helpful.

 

Thanks.

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