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LTM8068 Recommended for New Designs
The LTM8068 is a 2kV AC isolated flyback μModule® (power module) DC/DC converter with LDO post regulator. Included in the package are the switching controller...
Datasheet
LTM8068 on Analog.com

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Transient Output voltage simulation

		
	
				

			

									
					    Nawaf
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Jul 14, 2024 
				
			
			
		
    
		
		                     
				
        		
    
		    
		    		    
    
		      		            		        
    Category: Hardware
    
    		        		            		    
    Product Number:  LTM8068  
    
    		        		    		    
    
		    		    
		    			
    
			    
    Dear Engineers,
    

    I have an issue with LTM8068 DC/DC converter, that is as i  run tranisent simulation with input of 28VDC 
    

    given that I choose the resistors values as specified in the datasheet, the output doesn't settle at 5V 
    

    it increase to higher values with transient time is 50ms.
    

    

    

    ltm8068_test.asc
    

     
    
			
    
			
									
		                             
                        

    
    
                                            
                 hardware
                
                                                    
                 Isolated µModule Converters
                
                                                    
                 µModule Regulators
                
                                                    
                 LTM8068
                
                                
            
    
    
    
		
    

				
				        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                                                    
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			


				
	









	
      
	

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                on Jul 14, 2024 9:10 AM
            
            
						
			            		
        
		
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        Hello Nawaf, 
        

        the LTM8068  requires a minimum load to stabilize the output voltage. See the corresponding chapter on page 14 and the correspondig graph on page 6 of the datasheet.
        

        In your simu, you have not load at all at the output. Add the required minimum load (e.g. 500 Ohm between Vout1 and VoutN), and the output will stabilize at the intended voltage.
        

        best regards
        

        Achim
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
				
				
				
		
		
        
			
		
        
	
        

        

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