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LTC6806 Production
The LTC6806 is a fuel cell monitor that measures up to 144 Series Connected Fuel cells with a total measurement error of less than 15mV. The LTC6806 includes...
Datasheet
LTC6806 on Analog.com

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LTC6806 - CELL Monitor - Open Wire Detection

		
	
				

			

									
					    JVigg
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on May 24, 2024 
				
			
			
		

		
		                     
				
        		

		    
		    		    

		      		            		        
Category: Datasheet/Specs

    		        		            		    
Product Number:  LTC6806  

    		        		    		    

		    		    
		    			

			    
Hello, 


I am working on a design with LTC6806. I am having issues with the open wire detection.


I am able to get a single open wire to read properly but i am unable to detect multiple open wires at a time. 


Additionally, given that the LTC6806 is less commonly used IC, i was wondering if there were some issues with the datasheet. I have noticed that the algorythim for the open wire detection is counter to the other LTC68xx monitoring ICs. 


On page 28 the ADOW command is run with PUP=0 for pullup and PUP=1 for pulldown but i think this is a typo. 

			

			
									
		                             
                        

    

                                            
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                 Datasheet/Specs
                
                                                    
                 Multiple Open Wire Detection
                
                                                    
                 Open Wire Algorithm
                
                                                    
                 LTC6806
                
                                        
                                            
                
                
                                        
                                            
                
                
                                
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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Aug 8, 2024 4:15 AM
            
            
						
			            		
    
		
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    Hello  
    

    I am sorry for the late reply.
    

    PUP Bit seems to be active low, i.e. PUP=0 then Pull-up applied.
    PUP=1 then Pull-Downs activated. 
    

     
    

    With ADOW you compare each cell voltage during PUP and PDOWN and then decide if OW is there. As in your attached capture above. 
    Could you not see the voltage differences at multiple cells which are OW'ed?
    

    If you input capacitances are large, you may need more time, achieved thru sending multiple ADOW commands.  As mentioned in the datasheet. 
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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