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LT3120 Recommended for New Designs
The LT3120 is a high efficiency 26V monolithic buck-boost converter. Extensive feature integration and very low resistance internal power switches minimize...
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LT3120 on Analog.com

LTC2927 Recommended for New Designs
The LTC2927 provides a simple solution to power supply tracking and sequencing requirements. By selecting a few resistors, the supply can be configured...
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LTC2927 on Analog.com

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LT3120 Output Voltage Tracking

		
	
				

			

									
					    MNixon442
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on Feb 20, 2026 
				
			
			
		

		
		                     
				
        		

		    
		    		    

		      		            		        
Category: Hardware

    		        		            		    
Product Number:  LT3120  

    		        		    		    

		    		    
		    			

			    
Hi, 


I'm looking for a way to have the LT3120 output voltage track a battery voltage such that the 3120 output stays ~0.5V above the battery. I understand that the FB regulation loop uses an error amplifier to adjust the output in order to maintain Vfb (0.795V). Can something like the LTC2927 power supply tracking controller achieve what I'm trying to do?


Best regards, 


Matt

			

			
									
		                             
                        

    

                                            
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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Feb 26, 2026 5:39 AM
            
            
						
			            		
    
		
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    Hello, 
    The LTC2927 is designed primarily for ramp tracking and sequencing, not precision offset regulation. There are simpler and more robust ways to do this directly at the LT3120 FB pin.
    Because the LT3120 regulates FB to 0.795 V, you can directly “add” the battery voltage by feeding a scaled version of VBAT into FB through a resistor, along with the normal VOUT divider or choose an output that is above your battery voltage and use this to calculate the feedback resistors.
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
						
				
				
				
		
		
    
			
		
    
	
    

    

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