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LT1937 Production
The LT1937 is a step-up DC/DC converter specifically designed to drive white LEDs with a constant current. The device can drive two, three or four LEDs...
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LT1937 on Analog.com

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LT1937 - what is a maximum current to drive 1 power led?

		
	
				

			

									
					    MaciekM
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Jan 16, 2023 
				
			
			
		
    
		
		                     
				
        		
    
		    
		    		    
    
		      		            		        
    Category: Hardware
    
    		        		            		    
    Product Number:  LT1937 
    
    		        		    		    
    
		    		    
		    			
    
			    
    Hi, 
    

    Can LT1937 provide current  300mA? In case I will use Rset = 0.5Ω, the current shall ~250mA (based on LTSpice simulation (Vin=2,5V).
    

    The question if the LT1937 can drive this value of current?
    

    

    best regards
    

    

    M.M.
    
			
    
			
									
		                             
                        

    
    
                                            
                 Step-Up (Boost) LED Drivers
                
                                                    
                 hardware
                
                                                    
                 LT1937
                
                                                    
                 LED Driver IC
                
                                
            
    
    
    
		
    

				
				        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                                                    
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			


				
	









	
      
	

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							FormerMember
					
      
		
      
		    
		    		    
			
				
									FormerMember
							        
			
			
			
    
            
						
                            
            
            				
            
                on Jan 16, 2023 6:21 PM
            
            
						
			            		
    
		
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    Hello,
    

    No, it cannot. The maximum switch current it can withstand is 320 mA, and it will not be able to provide a 300mA output.
    

    

    Regards,
    

    Jhun
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
						
				
				
				
		
		
    
			
		
    
	
    

    


	

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                on Jan 17, 2023 6:14 AM
            
            
												
						in reply to FormerMember
					
										
			            		
      
		
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      Hi JHun,
      

      

      thanks, what about LT1932?  I see maximum switch current 780mA?
      

      Or LT3593? 
      

      May I used them for current 300mA max?
      

      

      I'm looking for small package SOT or TSOP 6 pin max
      

      

      best regards
      

      Maciek
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
				
				
				
		
		
      
			
		
      
	
      

      

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							FormerMember
					
      
		
      
		    
		    		    
			
				
									FormerMember
							        
			
			
			
            
						
                            
            
            				
            
                on Jan 18, 2023 1:21 AM
            
            
												
						in reply to MaciekM
					
										
			            		
      
		
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      MaciekM said:
      Or LT3593?
      

      LT3593 is not feasible since it has a minimum input voltage of 2.7V
      

      

      MaciekM said:
      what about LT1932?
      

      I think you should try to use LTSpice and see if the current is okay. Switch current is dependent on Vin, Vout and Iout you would need.
      

      

      Regards,
      

      Jhun
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
				
				
				
		
		
      
			
		
      
	
      

      

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