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LT7101 Recommended for New Designs
The LT7101 is a high efficiency, monolithic synchronous step-down DC/DC converter utilizing a constant frequency, average current mode control architecture...
Datasheet
LT7101 on Analog.com

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LT7101: What is CIN (CBULK) ?

		
	
				

			

									
					    riscy0000
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Dec 19, 2019 
				
			
			
		
    
		
		                     
				
        		
    
		    
		    		    
		    			
    
			    
    The Application side of the datasheet is little vague for recommending CBULK  minimum and typical capacitance. The test circuit is shown CIN/CBULK = 4.7uF but why?
    

    Can you please expand that area.
    

    Thanks
    
			
    
			
									
		                             
                        

    
    
                                            
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      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Jan 9, 2020 12:52 AM
            
            
						
			            		
      
		
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      The recommended value is based on the typical application circuit & for best performance after testing.  In most application, 4.7uF is enough. Certainly, you would want the output ripple and EMI to be as low as possible. Input capacitance has to be in the right amount in order to balance performance and cost (high cost if you go higher capacitance ratings).
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
						
				
				
				
		
		
      
			
		
      
	
      

      

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