Products Mentioned

AD723 Production
The AD723 is a low cost RGB-to-NTSC/PAL encoder that converts analog red, green, and blue color component signals into their corresponding luminance and...
Datasheet
AD723 on Analog.com

Thread Details

  • State Verified Answer
  • Replies 16 replies
  • Subscribers 79 subscribers
  • Views 2411 views
  • Users 0 members are here
Options
 
Related Content

        

            Post
             Go back to editing
        

    

    


    

    









		


















	
	
			
	
			
			
	
	
		

	    
	    
	    		
The color burst from AD723 seems to move on AD723 Eval Board.

		
	
				

			

									
					    Tamu
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on May 28, 2013 
				
			
			
		
    
		
		                    	    
    
        	    
    Thread Summary
    
                The user inquired about the variability of the color burst start point on the AD723 Eval Board (AD723EB rev.B). The engineer confirmed that the maximum phase error due to asynchronous operation is one cycle of 4FSC (90 degrees at 3.579545 MHz), and variations due to temperature, process, and voltage are negligible. The user should focus on the accuracy of the external 4FSC oscillator (14.318180 MHz) for assessing the burst start point variation.
                        	    
    
                
                     AI Generated Content
                
    	    
    
             
				
        		
    
		    
		    		    
		    			
    
			    
    Hello,
    
 
    I have questions about AD723.
    The start point of color burst from AD723 seems to move on AD723 Eval Board (AD723EB rev.B).
    Could you see attached file "Color_burst_AD723_rev01.xlsx" for more detail?
    
 
    Thank you!
    
 
    Best regards.
    Tamu
    
			
    
			
									
		                             
                        

    
    
                                            
                 Video Products
                
                                                    
                 ad723eb
                
                                                    
                 Video Encoders
                
                                                    
                 burst
                
                                                    
                 ad723
                
                                        
                                            
                
                
                                        
                                            
                
                
                                        
                                            
                
                
                                
                    Show More
            
    
    
    
		
    

				
							Color_burst_AD723_rev01.xlsx
					        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                        
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			








	
	
	
	



Parents
	
      
	

    • 
	
      



	
		
	
	



      
	
      
		
      
							
					
      
		
      
		    
		    		    
			
				
									
							        
			
			
			
        
            
						
                            
            
            				
            
                on May 30, 2013 1:43 AM
            
            
						
			            		
        
		
										0
					
	
        

		
		
        
		
        
                                
                                                            
        
					
        Hello Jonathan,
        
 
        Thank you for your reply.
        
 
        I thought I'd like to try synchronous operation.
        But unfortunatly, I can not try it  because of our SG and system.
        
 
        About my first question, I understood the asynchronous 4FSC causes moving the start point of color burst.
        
 
        Please let me confirm about my second question.
        >How much phase does the start point of color burst move at the maximum?
        >Is it one subcarrier (3.579545MHz for NTSC)?
        
 
        Is one subcarrier (3.579545MHz for NTSC) right?
        or is it one 4FSC (14.318 180 MHz for NTSC)?
        
 
        Thank you!
        
 
        Best regards.
        Tamu
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
						
				
				
		
		
        
			
		
        
	
        

        

        • 

	
      



Reply

        


      • 
	
        



	
		
	
	



        
	
        
		
        
							
					
        
		
        
		    
		    		    
			
				
									
							        
			
			
			
          
            
						
                            
            
            				
            
                on May 30, 2013 1:43 AM
            
            
						
			            		
          
		
										0
					
	
          

		
		
          
		
          
                                
                                                            
          
					
          Hello Jonathan,
          
 
          Thank you for your reply.
          
 
          I thought I'd like to try synchronous operation.
          But unfortunatly, I can not try it  because of our SG and system.
          
 
          About my first question, I understood the asynchronous 4FSC causes moving the start point of color burst.
          
 
          Please let me confirm about my second question.
          >How much phase does the start point of color burst move at the maximum?
          >Is it one subcarrier (3.579545MHz for NTSC)?
          
 
          Is one subcarrier (3.579545MHz for NTSC) right?
          or is it one 4FSC (14.318 180 MHz for NTSC)?
          
 
          Thank you!
          
 
          Best regards.
          Tamu
          
			
          

		
			
	      

		
		
	
          
	
          
		
          
			
		
          
	
          
	
          
		
						
						
				
						
				
				
		
		
          
			
		
          
	
          

          

          • 


        


Children
	
        No Data