Products In This Thread

AD9117 Production
The AD9114/AD9115/AD9116/AD9117 are pin-compatible dual, 8-/10-/12-/14-bit, low power digital-to-analog converters (DACs) that provide a sample rate of...
Datasheet
AD9117 on Analog.com

  • State Suggested Answer
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 24 subscribers
  • Views 252 views
  • Users 0 members are here
Options
Related 

        

            Post
             Go back to editing
        

    

    


    

    









		












	
	
			
	
			
		
	
	
		

		
Placement of AD9117 FSADJ pin resistor and capacitor



		

			

									
					    knj
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Feb 20, 2023 
				
			
			
		
    

				
		
    
		    		    
		    
		    		            		        
    Category: Hardware
    
    		        		            		    
    Product Number:  AD9117 
    
    		        		    		    	
			
    Hello
    

    I have a question about the location of the resistor and capacitor to be placed on the FSADJ pin of the AD9117.
    

    Datasheet P45 describes the Rset resistor connected to FSADJ.
    Here, when mounting 4kΩ or more, it is described to divide the resistance into 4kΩ + 12kΩ and add a 1μF capacitor from 4kΩ to Ground.
    

     
    

    Is the recognition correct with the configuration shown below?
    If I'm wrong, please let me know the correct configuration.
    

     
    

    I would appreciate it if you could reply.
    

    Best Regards,
    Knj
    
								
    

				
				
		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    


	
    
		






			

			
    
			
    Top Replies
    
		
    

		
    
			
		
    
		
    
					
    
	
	
    















    
	
    
	
    
					



			


				
	









	
      
	

    • 
	
      



	
			
		
	



      
	
      
		
      
							
					
      
		
      
			
													0
							
			
				
									
							        
			
			
			
      •  Analog Employees  
      
            
			                            
                        
                on Mar 14, 2023 5:52 AM
            
            
					
      
	
      

		
		
      
					
      Hi Knj,
      

       
      

      The configuration should be similar to the schematic found in page 5 of AD9117 Eval-board schematic (IOUT Network and FSADJ1). Under the jumper JP12, the 12kΩ resistor can be directly connected to GND, and on the other branch is the 4kΩ resistor and the capacitor. This is so that there's will still be a DC path for the FSADJ current to GND. 
      

       
      

      Note that this configuration isn't required for a resistance greater than 4kΩ. You can still connect a resistance up to 16kΩ directly to FSADJ pin without splitting it into 4kΩ plus the additional resistance. The configuration is just helpful for the adjustment span of IxOUTFS and certain applications such as small signal multiplying applications.
      

       
      

      Warm regards,
      

       
      

      Marco
      
			
      

		
		
		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
						
						
				
				
		
		
      
			
		
      
	
      

      

      • 

	

    • 
	
      



	
		
	
	



      
	
      
		
      
							
					
      
		
      
			
													0
							
			
				
									
							        
			
			
			
        
            
			                            
                        
                on Mar 17, 2023 6:58 AM
            
            
												
						in reply to JMMina
					
									
        
	
        

		
		
        
					
        Hi, Marco
        

        Thank you for your reply.
        I checked the circuit diagram of the evaluation board, and 12kΩ and 4kΩ are connected in parallel.
        Will a current equivalent to Rset = 16kΩ flow in this configuration?
        

        Also, the datasheet recommends 1uF for the additional capacitor, but the schematic for the evaluation board is 10pF.
        Which do you prefer?
        

        I would appreciate it if you could reply.
        

        Best Regards,
        Knj
        
			
        

		
		
		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
						
				
				
		
		
        
			
		
        
	
        

        

        •