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ADXL1002 Recommended for New Designs
The ADXL1001/ADXL1002 deliver ultralow noise density over an extended frequency range with two full-scale range options, and are optimized for industrial...
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ADXL1002 on Analog.com

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Weird lectures with ADXL100xZ the evaluation board after 5k Hz

		
	
				

			

									
					    Juand2
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on Mar 13, 2026 
				
			
			
		

		
		                     
				
        		

		    
		    		    

		      		            		        
Category: Hardware

    		        		            		    
Product Number:  ADXL1002  

    		        		    		    

		    		    
		    			

			    
Hi, I'm using the ADXL1002 to sense mechanical vibrations (frequency and amplitude). For the test, we are using a certified shaker table to excite the system from 100Hz to 10 kHz with a force of 1G. We are having good lectures until we reach 1K Hz with our base, as is possible to see here: 


 




To check if it is something related to the mount, we tested with the evaluation board ADXL100xZ that has an aluminum cube and this is what we got: 



 

Despite the amplitude of the lower frequencies, which I suppose is for impedance matching between the ADC and the accel, it should be constant for all frecuencies but we are having this erratic behaviour after 5KHz. With this eval kit, there should be a constant graph like in the datasheet: 

 




The ADC is the AD4004BRMZ. We also connected the accel trought a second-order RC filter and an ADA4805 opamp in a voltage follower configuration. What could be affecting the result at high frequency, even with the EV board? 

Is the amplitude smaller due to anything else?

			

			
									
		                             
                        

    

                                            
                 hardware
                
                                                    
                 accelerometers
                
                                                    
                 adxl1002
                
                                                    
                 Sensors and MEMS
                
                                
            

    
    
		


				
				        
        		

			
						
									
												
			
			
                        
                                    
                        
                        
                        
            
			            
						
						
			
			
			
			
		


        
        
        
    
					

			





















	

	

					



			


				
	









	
    
	

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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Mar 17, 2026 6:05 AM
            
            
						
			            		
    
		
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    Hello  thanks for reaching out!

    Could you share if possible, some pictures of both setups (blue and green graph) to check the mounting.

    I would also try to run the test placing the eval board/sensor in different directions/axis in order to see how this affects the waves.

    Could you also share your schematic to crosscheck the supply, filter and other details?


    here you have a reference design with a user guide: CN0533 Circuit Note | Analog Devices
     
    

    

    Mechanical Mounting
    

    

    

    

    The accelerometer used in this reference design, ADXL1002, is an ultra-low noise and high bandwidth sensor. To achieve the best performance, a proper mechanical design is required to deliver vibration signal from the measurement point to the sensor. Careful considerations in design of EVAL-CN0533-EBZ PCB has been taken to avoid vibration signal distortion to the sensor due to mechanical resonance of the PCB structure. To best deliver the vibration signal from the measurement point to the PCB, we have designed EVAL-XLMOUNT1. This mechanical interface is optimized to have a 3dB flat mechanical response of up to 20 kHz. Therefore, by utilization of EVAL-XLMOUNT1, the vibration signal will be adequately coupled with the sensor. The following steps describe how to use EVAL-XLMOUNT1 with EVAL-CN0533-EBZ.
    

      

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      Using four 4-40 3/8” screws, securely mount the EVAL-CN0533-EBZ to the EVAL-XLMOUNT1 mechanical interface. For optimum performance, use all four screws.
      

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      Firmly mount EVAL-XLMOUNT1 to the vibration platform or shaker table using a M6 or similar diameter screw. Note that the sensitivity direction of the ADXL1002, as shown in the figure above, is aligned with the platform’s main vibration direction.
      

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      Follow steps for proper sensor connection outlined above.


      

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    Keep us posted, un saludo.

    Mario SM
    

    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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                on Mar 17, 2026 3:43 PM
            
            
												
						in reply to MarioSM
					
										
			            		
    
		
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    Hi, thanks for answering. It was something with an opamp. Can you tell me what the material of the EVAL PCB is? Also, can you confirm which was the amplitude value used during this test?  
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Mar 20, 2026 10:10 AM
            
            
												
						in reply to Juand2
					
										
			            		
    
		
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    Hi there, good to know you've solved the problem. To facilitate anyone having a similar problem to yours and looking at this forum, could you share more information about the specific cause of the problem and what steps you took to resolve it?
    

    To answer your questions, the evaluation board is a copper-clad laminate made out of FR-4 epoxy glass and copper traces. The data in the figure you posted was taken with an amplitude of 1g.

    Let us know if there is anything else we can do to assist you.
    

    Un saludo, Nico
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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