Thread Details

  • State Verified Answer
  • +1 person also asked this people also asked this
  • Replies 1 reply
  • Subscribers 33 subscribers
  • Views 82 views
  • Users 0 members are here
Options
Related 

        

            Post
             Go back to editing
        

    

    


    

    









		


















	
	
			
	
			
		
	
	
		

	    
	    
	    		
cannnot readback data register

		
	
				

			

									
					    tmaceo
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Nov 9, 2025 
				
			
			
		
    
		
		                    	    
    
        	    
    Thread Summary
    
                The user is troubleshooting readback issues with the AD5764 DAC after writing to the data register. The support engineer suggests that reading back the register should not return zeros if the write was successful and recommends trying the readback with the LDAC pin tied high, as per the 'Readback Operation' section in the datasheet.
                        	    
    
                
                     AI Generated Content
                
    	    
    
             
				
        		
    
		    
		    		    
    
		      		            		        
    Category: Software
    
    		        		            		    
    Product Number:  AD5764  
    
    		        		    		    
    
		    		    
		    			
    
			    
    I am attempting to read back the data register after writing a value to it.    I can read back the fine grain register after writing it, so fairly confident SPI timing is good.      My LDAC pin is tied low, so that the DAC output is updated immediately when sync goes high.   Does this mean that reading back the register will return zeros?
    
			
    
			
									
		                             
                        

    
    
                                            
                 software
                
                                                    
                 ad5764
                
                                                    
                 Precision D/A Converters
                
                                                    
                 Voltage Output D/A Converters
                
                                                    
                 Multichannel Voltage Output D/A Converters
                
                                
            
    
    
    
		
    

				
				        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                        
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			








	
	
	
	



Parents
	
      
	

    • 
	
      



	
			
		
	



      
	
      
		
      
							
					
      
		
      
		    
		    		    
			
				
									
							        
			
			
			
      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Nov 10, 2025 10:30 PM
            
            
						
			            		
      
		
										+1
					
	
      

		
		
      
		
      
                                
                                                            
      
					
      Hi  
      

      Thank you for using AD5764.
      Reading back the register after the DAC output is updated doesn't necessarily mean that you'll only read zeros.
      Have you tried tying the LDAC pin high then reading the contents of the register to confirm successful readback?
      The "Readback Operation" of the datasheet has an example on how to implement the readback sequence.
      

      Hope this helps.
      

      Regards,
      Flynn
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
				
						
						
				
				
		
		
      
			
		
      
	
      

      

      • 

	
    



Reply

      


    • 
	
      



	
			
		
	



      
	
      
		
      
							
					
      
		
      
		    
		    		    
			
				
									
							        
			
			
			
      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Nov 10, 2025 10:30 PM
            
            
						
			            		
      
		
										+1
					
	
      

		
		
      
		
      
                                
                                                            
      
					
      Hi  
      

      Thank you for using AD5764.
      Reading back the register after the DAC output is updated doesn't necessarily mean that you'll only read zeros.
      Have you tried tying the LDAC pin high then reading the contents of the register to confirm successful readback?
      The "Readback Operation" of the datasheet has an example on how to implement the readback sequence.
      

      Hope this helps.
      

      Regards,
      Flynn
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
				
						
						
				
				
		
		
      
			
		
      
	
      

      

      • 


    


Children
	
    No Data
    

		
			
    

    





		
    
		
    
			
      
				
    • 
					
												
						
						
						
						
						
						
						

																										
						
						

					
					
					
				
      •