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LTM4637 Recommended for New Designs
The LTM4637 is a complete 20A output high efficiency switch mode step-down DC/DC μModule (power module) regulator. Included in the package are the switching...
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Will It Generate 5.5 out from 12V

		
	
				

			

									
					    SGCH
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on Jun 2, 2026 
				
			
			
		

		
		                     
				
        		

		    
		    		    

		      		            		        
Category: Hardware

    		        		            		    
Product Number:  LTM4637  

    		        		    		    

		    		    
		    			

			    


Hello Team,


I have a question regarding the LTM4637 µModule regulator.


I am trying to generate a 5.5 V output from a 12 V input supply. Based on the datasheet, the device supports 5.5 V output with load currents in the range of approximately 10–15 A.


I performed a simulation in LTspice, and while I am able to obtain an output close to 5.5 V, I am seeing some variation, and the output is not stable or exactly at the expected value.


For the feedback network:


    

  • I adjusted the VFB resistor to ~7.5 kΩ
    • 

  • When I reduce the value further, the output does not behave as expected and becomes unstable/misaligned
    • 



I would like to understand:


    

  1. Whether the LTM4637 can reliably generate 5.5 V from a 12 V input under these conditions
    2. 

  2. If my feedback resistor selection is correct
    3. 

  3. Whether there are any design considerations that I might be missing in simulation
    4. 



I have attached my schematic for reference. Kindly review it and let me know if there are any mistakes or improvements needed.




Thanks,


Surya


/resized-image/__size/2776x980/__key/communityserver-discussions-components-files/330/pastedimage1780408772187v1.png


 



			

			
									
		                             
                        

    

                                            
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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Jun 2, 2026 12:43 PM
            
            
						
			            		
    
		
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    Hi  ,
    

    Can you upload your LTspice schematic, symbol and model files? Zip up and drag to this window. 
    

    mike
    LTspice Team
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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                on Jun 3, 2026 2:04 AM
            
            
						
			            		
    
		
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    Hi MStokowski,
    

    

    Please find the attached image of the LTspice simulation. Here, I am not able to generate the exact 5.5 V; I am getting around 5.4 V
    

    

     
    

    

    

    Thanks,
    

    Surya
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Jun 3, 2026 1:57 PM
            
            
						
			            		
    
		
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    Hi  ,
    

    It's best if you upload your schematic files. Drag to the window, or Choose Insert > Image/Video/File and then click upload in window that appears.
    

    mike
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
						
				
				
				
		
		
    
			
		
    
	
    

    

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                on Jun 4, 2026 5:04 AM
            
            
						
			            		
    
		
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    Hi Team,
    

    Please find the attached simulation files for your reference. Kindly review and provide your feedback.
    

    

    

    LTM4637.ascLTM4637.rawLTM4637.op.raw



    
    
    
        Fullscreen
        LTM4637.log
        Download
    
    
    
    LTspice 24.1.8 for Windows
Circuit: C:\Users\suryaganesh.c\Documents\LTspice\LTM4637.net
Start Time: Thu Jun  4 14:36:42 2026
solver = Normal
Maximum thread count: 8
tnom = 27
temp = 27
method = trap
Direct Newton iteration failed to find .op point.  (Use ".option noopiter" to skip.)
Starting Gmin stepping
Gmin = 10
Gmin = 1.07374
Gmin = 0.115292
Gmin = 0.0123794
Gmin = 0.00132923
Gmin = 0.000142725
Gmin = 1.5325e-05
Gmin = 1.6455e-06
Gmin = 1.76685e-07
Gmin = 1.89714e-08
Gmin = 2.03704e-09
Gmin = 2.18725e-10
Gmin = 2.34854e-11
Gmin = 2.52173e-12
Gmin = 2.70769e-13
Gmin = 0
Gmin stepping succeeded in finding the operating point.

Total elapsed time: 4.864 seconds.

Files loaded:
C:\Users\suryaganesh.c\Documents\LTspice\LTM4637.net
C:\Users\suryaganesh.c\AppData\Local\LTspice\lib\sub\LTM4637.sub


    

    


    

    

    

    

    

    

    

    

    Thanks,
    

    Surya
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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