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LTC2992 programming issue



		

			

									
					    ihsan
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Jun 21, 2022 
				
			
			
		
    

				
		
    
		    		    
		    
		    		            		        
    Category: Hardware
    
    		        		        		    		    	
			
    Hello,
    

    We have a stingray platform. I am trying to powerup the device by following the powerup procedure in the link below. 
    

    https://wiki.analog.com/resources/eval/user-guides/stingray/userguide#configuring_the_ltc2992 . According to wiki, writing 0x00 to  0x96 and 0x97 registers of LTC2992 will blink the orange led on the board.
    

    However when i try to program LTC2992 over I2C, device do not respond. I also tried to scan i2c addresses on the board with Arduino i2c_scanner code, but Arduino could not find any i2c address.
    

    All of these means that the chip is broken? LTC2992 datasheet  says, chip requires repeated start conditon for read operations. Does LTC2992 also require repeated start condition for just write operation?
    

    thank in advance.
    

     
    
								
    

				
				
		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    


	















    
	
    
	
    
					



			


				
	









	
      
	

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      •  Analog Employees  
      
            
			                            
                        
                on Jun 22, 2022 5:57 PM
            
            
					
      
	
      

		
		
      
					
      Greetings Ihsan,
      

          The repeated start is not used for writes, but if you're address scan is coming up empty then there is something wrong.  There is a possibility that the part could be faulty, but that is pretty rare.  The first thing to check is that the the board (and the part) is powered up.  Next, if you can provide scope shots of SDA and SCL, we might be able to troubleshoot more thoroughly.
      

      Thank you and best regards,
      

      Brad  
      
			
      

		
		
		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
						
						
				
				
		
		
      
			
		
      
	
      

      

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                on Jul 19, 2022 12:17 PM
            
            
												
						in reply to blovell
					
									
        
	
        

		
		
        
					
        Hello, sorry for late response. We handled LTC2992 programming. It was our mistake. Now we have another problem. First We programmed LTC 2992, next we pulsed power_up_down signal and we saw orange led blinks. Then, we programmed ADAR1000's with the recommended register data.After that, When we try to pulse 5V_CTRL signal, the orenge led starts to wink forever. There is no green led. What is the problem here? How long should be the pulse duration? there is no information about that in the link that i provided.
        

        Thanks in advance.
        

        Ihsan.
        
			
        

		
		
		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
						
				
				
		
		
        
			
		
        
	
        

        

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