Products In This Thread

AD9235 Production
The AD9235 is a family of monolithic, single 3 V supply, 12-bit, 20/40/65 MSPS analog-to-digital converters. This family features a high performance sample...
Datasheet
AD9235 on Analog.com

AD8132 Production
The AD8132 is a low cost differential or single-ended input to differential output amplifier with resistor set gain. The AD8132 is a major advancement...
Datasheet
AD8132 on Analog.com

  • State Verified Answer
  • Replies 3 replies
  • Subscribers 44 subscribers
  • Views 775 views
  • Users 0 members are here
Options
Related 

        

            Post
             Go back to editing
        

    

    


    

    









		












	
	
			
	
			
		
	
	
		

		
AD9235 setup



		

			

									
					    anapoly
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Dec 3, 2014 
				
			
			
		
    

				
		
    
		    		    
		    
		    	
			
    Let me confirm how to set up　AD9235 (12bit AD Conveter) with AD8132(Differential Amp.).
    
 
    My question is the relation between SENSE, VREF in AD9235 and VCOM in AD8132.
    
 
    In my understanding, VREF can be connected with external voltage as an input. 
    
 
    So if I set the SENSE as AVDD, I can get 2 x VCOM accordingto the data sheet.
    
 
    If I set the VCOM as +1.5V by volume, I can get 3Vp-p output from AD9235, am I correct?
    
 
    Or I may be able to set SENSE using external resistor(R1:1K, R2:2kohm) to get VREF as 1.5V
    
 
    like Figure40. Then I can get the same 3Vp-p, am I corrct? 
    
									
			        
		
    

				
				
		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    


	
    
		
	
    















    
	
    
	
    
					



			








	
	
	
	



Parents
	
      
	

    • 
	
      



	
		
	
	



      
	
      
		
      
							
					
      
		
      
			
													0
							
			
				
									
							        
			
			
			
      •  Analog Employees  
      
            
			                            
                        
                on Dec 5, 2014 10:01 PM
            
            
					
      
	
      

		
		
      
					
      Hi,
      
 
      You are correct that you can provide an external VREF when SENSE is tied to AVDD.  The AD9235 is characterized for operation between 1 to 2Vpp differential.  Greater voltages like 3Vpp differential can be accommodated, but distortion performance will degrade.
      
 
      The internal reference generator has not been characterized to output 1.5 V, so I would not depend on that to generate the VREF in that case. 
      
 
      You may gain some headroom with higher analog supply voltage, which in-turn will increase the Vcm that the AD9250 outputs and give the input sampling circuitry a little more margin.  
      
 
      Anthony  
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
						
				
				
		
		
      
			
		
      
	
      

      

      • 

	
    



Reply

      


    • 
	
      



	
		
	
	



      
	
      
		
      
							
					
      
		
      
			
													0
							
			
				
									
							        
			
			
			
      •  Analog Employees  
      
            
			                            
                        
                on Dec 5, 2014 10:01 PM
            
            
					
      
	
      

		
		
      
					
      Hi,
      
 
      You are correct that you can provide an external VREF when SENSE is tied to AVDD.  The AD9235 is characterized for operation between 1 to 2Vpp differential.  Greater voltages like 3Vpp differential can be accommodated, but distortion performance will degrade.
      
 
      The internal reference generator has not been characterized to output 1.5 V, so I would not depend on that to generate the VREF in that case. 
      
 
      You may gain some headroom with higher analog supply voltage, which in-turn will increase the Vcm that the AD9250 outputs and give the input sampling circuitry a little more margin.  
      
 
      Anthony  
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
						
				
				
		
		
      
			
		
      
	
      

      

      • 


    


Children
	
    No Data