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The LT1241 series devices are 8-pin, fixed frequency, current mode, pulse width modulators. They are improved plug compatible versions of the industry...
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LT1241 on Analog.com

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Demo application Simulation Failed using LT1241 to generate Isolated Power Supply

		
	
				

			

									
					    GoldSeed
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on Jul 15, 2025 
				
			
			
		

		
		                     
				
        		

		    
		    		    

		      		            		        
Category: Datasheet/Specs

    		        		            		    
Product Number:  LT1241 

    		        		    		    

		    		    
		    			

			    
Hi, there,




I copied all the components used in datasheet Page14 as demo application, but simulation result is not as expected, that output power is still zero, with many spikes included.


See the circuit attached, and result.


Please correct me if not corrected connected.


  

			

			
									
		                             
                        

    

                                            
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                 Datasheet/Specs
                
                                                    
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                 Power Control
                
                                                    
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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Jul 15, 2025 3:32 PM
            
            
						
			            		
    
		
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    Hello GoldSeed,
    

    I see a number of mistakes. I would suggest starting with a working example. Start LTspice, choose File/New Schematic, press F2 (which is Edit/Component), type LT1241 and then click “Open Example Circuit” button. This will bring up an example schematic. Click the running man to verify the circuit is working. From there, you can modify.
    

    Kurk
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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                on Jul 19, 2025 1:18 AM
            
            
						
			            		
    
		
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    Hi, tks for quick response.
    

    Per ur suggestion, i checked about Example Circuit, it helped. For comparison, my circuit is very similar with it, except the last isolated ground, which LTSpice could not run correctly.
    

    So I changed it to triangle Ground instead, it worked.
    

    tks again.
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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