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ADP1046 Not Recommended for New Designs
The ADP1046 is a flexible, digital secondary side controller designed for ac-to-dc and isolated dc-to-dc secondary side applications. The ADP1046 is pin...
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ADP1046 on Analog.com

ADP1046A Recommended for New Designs
The ADP1046A is a flexible, digital secondary side controller designed for ac-to-dc and isolated dc-to-dc secondary side applications. The ADP1046A is...
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ADP1046A on Analog.com

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How does the adp1046 keep zero crossing.



		

			

									
					    RVolkov
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Sep 20, 2016 
				
			
			
		
    

				
		
    
		    		    
		    
		    	
			
    Right now we are testing HB LLC converter based on adp1046 CPU.
    
 
    We had observed spikes on the secondary side while adp1046 changes frequency to keep needed output voltage.
    
 
    While frequency is steady spikes absent.  We consider that the periodical zero crossing failure causes spikes.
    
 
    The question is how does CPU follow the actual zero crossing during control process?
    
 
    How important is the digital filters adjustment in GUI (currently we are in default  setting)?
    
 
    Thanks
    
									
			        
		
    

				
						
        

    
    Tags: 
                                            
                 adp1046a
                
                                                    
                 llc
                
                                                    
                 adp1046
                
                                                    
                 Digitally Programmable Regulators
                
                                                    
                 Step-Down (Buck) Regulators
                
                                
            
    
    
    

		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    
















    
	
    
	
    
					



			


				
	









	
      
	

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      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Sep 20, 2016 7:57 PM
            

            
					
      
	
      

		
		
      
					
      Hi,
      
 
      What PWMs are you using to control the SR edges. If you are using SR1 or SR2 you have to adjust the dead time by moving the rising edge of SR1 and SR2 to the right by approximately 50-100ns based on typical data. The spikes are occurring due to non ZCS conduction of the SR fets. The easiest way, but may not be the most convenient, is to put a current probe on the secondary side and time the SR edges accordingly. You can refer to the waveforms figures 41-44 in UG-768 as an example. 
      http://www.analog.com/media/en/technical-documentation/user-guides/EVAL-ADP1046A_UG-768.pdf 
      
 
      For digital filter setting they are very important as they ensure the stability of your closed loop converter. You'll have to do a bode plot of the power supply and determine the phase margin and crossover frequency. Alternately if you don't have a network analyzer that does this you can check the transient response and check for potential oscillations, how fast is the settling time, under/over damped response etc.
      
 
      Lt Comm Data.
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
						
				
				
		
		
      
			
		
      
	
      

      

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                on Aug 2, 2018 11:35 AM
            

            
					
        
	
        

		
		
        
					
        This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

        Thank you,
        EZ Admin
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
				
						
						
				
				
		
		
        
			
		
        
	
        

        

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