AnsweredAssumed Answered

DOUTS IN ADXL375 - REG.

Question asked by agniteja@saitroniks.com on Jun 5, 2014
Latest reply on Jun 6, 2014 by agniteja@saitroniks.com

Hi All I have the following douts with reference to ADXL375

Conditions Vs & Vdd io= 3.3Volts

 

1. OUTPUT DATA RATES : As per the data sheet the output data rates is mentioned as 3200Hz = 3.2KHz = 0.312ms is the time duration.

     Does the ODR rate means the following. ..

     a. for every 0.312ms, 1 out of 32 FIFO blocks gets updated? (Each Block has 2 bytes registers for each axis )

     b. The entire 32 FIFO block are updated @ 0.312ms?

2. HOW SHOULD I CALCULATE THE MAXIMUM POWER CONSUMPTION OF ADXL375: The input supply is 3.3V common to Vs &      Vdd      io. The output data rate is 3200Hz. Number of Samples is 32.

     Max Power Consumed = (Power for Sampling 3 axis data & filling in the 32 FIFO@3200Hz ODR Power for transmitting the data      Through SPI @2MHZ Miscellaneous power for providing triggers). ?

     In Specifications it is given That for ODR > 100Hz, the typ. current consumption is 145uA. Does the current consumption increase      

     if the ODR is increased to 3200Hz?If so How Much?

3. AS PER THE APPLICATION NOTE NO.1266, PAGE 5 FIGURE 8 IN CAPTURING SHOCK PROFILE: There have been three wave forms

     shown in which Pre Trigger Samples are Shown. What is the difference between the 3 wave forms?. As per my understanding the      last      wave form captures the Shock Event Profile. What does the above 2 Wave forms Indicate.?

     As per the statment in application notes "Figure 8 shows the samples stored in the FIFO when set to different pre-trigger sample           lengths." does that mean is there a possibility to set pre - trigger sample length apart for regular sample length present in register      FIFO      CNTRL Register?Untitled.jpg

4. Is it possible to capture the shock curve profile for the above shock wave. If so how can we do that.?

 

Pl. bear with me if  my questions tend to be silly.

Thanking You

Looking Forward for you reply

AGNI

Outcomes