Products Mentioned

LTC1981 Production
The LTC1981/LTC1982 are low-power, self-contained N-channel MOSFET drivers. An internal voltage tripler allows gates to be driven without the use of any...
Datasheet
LTC1981 on Analog.com

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LTC1981 Switching Frequency

		
	
				

			

									
					    slastuka1
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Oct 2, 2019 
				
			
			
		
    
		
		                     
				
        		
    
		    
		    		    
		    			
    
			    
    Hi, 
    

    Is the switching frequency of the LTC1981 load dependent?  The datasheet spec is 600KHz given '10Kohm between load and ground'.
    

    Is the 'load' the gate output, or the drain-source current?  
    

    I'd love to load up the part so I could tweak that frequency up or a down a few ten's of KHz...
    

    Thanks
    
			
    
			
									    
    
			        
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[edited by: JValeriani at 6:50 PM (GMT 0) on 3 Oct 2019]
				
    
						
		                             
                        

    
    
                                            
                 High-Side Switches and MOSFET Drivers
                
                                                    
                 switching frequency
                
                                                    
                 Power Monitor  Control  and Protection
                
                                                    
                 LTC1981
                
                                                    
                 power by linear
                
                                
            
    
    
    
		
    

				
				        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                                                    
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			


				
	









	
      
	

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      •  Analog Employees  
      
            
						
                            
            
            				
            
                on Oct 14, 2019 11:39 AM
            
            
						
			            		
      
		
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      As I understand DS the word output's related to the pin GATE. Also, as I understand the DS, the charge pump' switching frequency is 600kHz measured at ATE. The value of  600kHz should not change as function of the load FET characteristics. Again, this is an internal charge pump, so frequency can not be adjusted. BTW why, exactly, do you want to reduce it? I will consult with the design department regarding your questions to make sure that my understating is correct. 
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
				
				
				
		
		
      
			
		
      
	
      

      

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                on Oct 14, 2019 12:27 PM
            
            
						
			            		
        
		
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        Thanks for the response.  We have a 24-bit ADC on the same board with a modulator running at 615-625KHz.  We worry 600KHz could creep into the ADC data because the two frequencies are close...  Thanks for checking into it.
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
				
				
				
		
		
        
			
		
        
	
        

        

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