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LT3476 Production
The LT3476 is a quad output DC/DC converter designed to operate as a constant-current source for driving high current LEDs. A ?xed frequency, current mode...
Datasheet
LT3476 on Analog.com

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LT3476 current calculation from Rsense



		

			

									
					    achinread
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Aug 23, 2019 
				
			
			
		
    

				
		
    
		    		    
		    
		    	
			
    Perhaps I missed it on the datasheet, but how exactly do you calculate the current to the LED from adjusting the value of Rsense? I do not see an equation. I assume that Rsense just sets the max/full scale current and making it smaller increases the max but also increases error as well?
    
									
			        
		
    

				
						
        

    
    Tags: 
                                            
                 Step-Down (Buck) LED Drivers
                
                                                    
                 LT3476
                
                                                    
                 current
                
                                                    
                 LED Driver IC
                
                                
            
    
    
    

		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    
















    
	
    
	
    
					



			








	
	
	
	



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      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Sep 2, 2019 10:36 PM
            
            
					
      
	
      

		
		
      
					
      Hi 
      

      The equation is Imax = Vadj / Rsns where Vadj is set from 10mV to 120mV using external voltage divider. This is discussed further on page 9 of the datasheet.
      

      Accuracy of current would be determined by the PCB layout,  Rsns and controller error which is guarantied to be 2.5% at the full scale of 105mV
      

      Regards, 
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
				
						
						
				
				
		
		
      
			
		
      
	
      

      

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      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Sep 2, 2019 10:36 PM
            
            
					
      
	
      

		
		
      
					
      Hi 
      

      The equation is Imax = Vadj / Rsns where Vadj is set from 10mV to 120mV using external voltage divider. This is discussed further on page 9 of the datasheet.
      

      Accuracy of current would be determined by the PCB layout,  Rsns and controller error which is guarantied to be 2.5% at the full scale of 105mV
      

      Regards, 
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
				
						
						
				
				
		
		
      
			
		
      
	
      

      

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