Products In This Thread

LTC2323-16 Production
The LTC2323-16 is a low noise, high speed dual 16- bit successive approximation register (SAR) ADC with differential inputs and wide input common mode...
Datasheet
LTC2323-16 on Analog.com

AD7380 Production
The AD7380/AD7381 are a 16-bit and 14-bit pin-compatible family of dual simultaneous sampling, high speed, low power, successive approximation register...
Datasheet
AD7380 on Analog.com

AD4630-16 Recommended for New Designs
The AD4630-16/AD4632-16 are 2-channel, simultaneous sampling, Easy Driveâ„¢, 2 MSPS or 500 kSPS successive approximation register (SAR), analog-to-digital...
Datasheet
AD4630-16 on Analog.com

AD7626 Production
The AD7626 is a 16-bit, 10 MSPS, charge redistribution successive approximation register (SAR) based architecture analog-to-digital converter (ADC). SAR...
Datasheet
AD7626 on Analog.com

ADA4945-1 Recommended for New Designs
The ADA4945-1 is a low noise, low distortion, fully differential amplifier with two selectable power modes. The device operates over a broad power supply...
Datasheet
ADA4945-1 on Analog.com

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LTC2323-16 temp co. fitting curve, INL curve?



		

			

									
					    starraytheon
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Sep 20, 2023 
				
			
			
		
    

				
		
    
		    		    
		    
		    		            		        
    Category: Datasheet/Specs
    
    		        		            		    
    Product Number:  LTC2323-16 
    
    		        		    		    	
			
    Hi Experts,
    

    I am using LTC2323-16, as I/V simultaneous sampling. For LTC2323, in spec page7, Offset error and Gain error temp curve are there, combine with Page11 fig2 transfer function curve to adjust system setting. Is it right solution for temp co. compensation? Besides, where I can find the INL curve? I mean, I need to find a solution to minimize the INL error using curve fitting. Basically, I want less than 2LSB INL. LTC2323-16 is good part for SPS and Bits demand. But INL is not good enough, or other new part can be introduced?
    

    I found that, in small signal, or say the mV level input, the INL is not stable, if we amplify the same signal, say X2, or X4, the INL will be improved. For this part, in near GND swing, the C cap tree induced more error caused SNR is dropped? What is the Ideal input range to get best INL performance?
    
									
			        
		
    

				
				
		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    


	















    
	
    
	
    
					



			


				
	









	
      
	

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      •  Analog Employees  
      
            
			                            
                        
                on Sep 20, 2023 11:37 AM
            
            
					
      
	
      

		
		
      
					
      The typical curves shown on page 7 are just that, typical. Offset and gain error will vary from part to part. If you want to calibrate out offset and gain error, you will need to measure each part. INL error will also vary from part to part. If you want to calibrate INL error, you will need to measure INL for each part. A far less costly solution would be to buy a better ADC.
      

      You do not say what sample rate you need. Take a look at AD7380 and AD4630-16.
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
				
						
				
				
		
		
      
			
		
      
	
      

      

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                on Sep 20, 2023 11:53 AM
            
            
												
						in reply to ADIApproved
					
									
        
	
        

		
		
        
					
        Thanks Ghoover!
        

        I need 4Msps, I learned that AD7380 and AD4630-16 before, seemed AD4630-16 is good, but this part SPI port is not good to FPGA ports, need more IO.
        

        If I change the input range to mid-REF level, it will help INL? Or the INL is not depended with voltage range, just vary with each part? If so, I will keep recent near GND range.
        

        More question, if error is vary form part to part, can we get the factory data of testing? say combined with physical goods?
        

        AD7626 is a good part, but single channel, I need Dual CH with Simultaneous Sampling.
        

        AD7380 is good for ADC core, but no S/H block, I need 4CH Amps to buffer, ADA4805 is good part I had learned, if for pre-amp, I am not sure ADA4807 or ADA4805 is best part to AD7380 buffer
        

        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
				
						
				
				
		
		
        
			
		
        
	
        

        

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        •  Analog Employees  
        
            
			                            
                        
                on Sep 20, 2023 1:20 PM
            
            
												
						in reply to starraytheon
					
									
        
	
        

		
		
        
					
        If you look at the THD, Harmonics vs Input Common Mode graph on page 6 of the data sheet, you will see that if you can keep the input common mode voltage constant at about 2.1V performance improves noticeably. If you drive the inputs with a fully differential amplifier, it is possible to keep the input common mode voltage constant. You don't say what your input signal BW is but something like the ADA4945-1 might work for you.
        

        It is not possible to provide INL plots with each individual part.
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
				
						
						
				
				
		
		
        
			
		
        
	
        

        

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                on Sep 22, 2023 11:36 AM
            
            
												
						in reply to ADIApproved
					
									
          
	
          

		
		
          
					
          Hi Ghoover,
          

          Thanks for strong support!
          

          I used InAmp in the front of LTC2323, I think that set InAmp REF to 2.1V will be great, but it will loss my small signal range, as my input is uni-direction, I will try to add MUX for REF to do range switching in further design.
          

          I have a question, if I do not change the recent design, as I have 2 set prototype is running, my system error will be +/- 12LSB in worst case? I saw page5 Note6 comments, I guess that maybe better @ My input signal is 10-20KHz, but I need to sampling the rising edge or falling edge, how can I use any tool to calculate the error?
          

          Thanks again!
          

          

          

          
			
          

		
			
	      

		
		
	
          
	
          
		
          
			
		
          
	
          
	
          
		
						
						
				
						
				
				
		
		
          
			
		
          
	
          

          

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          •  Analog Employees  
          
            
			                            
                        
                on Sep 22, 2023 11:52 AM
            
            
												
						in reply to starraytheon
					
									
          
	
          

		
		
          
					
          If zero-scale and full-scale error are calibrated out, your max error should be +/-12LSB. If zero-scale and full-scale are not calibrated out, then max error could be as high as 114LSB. This does not include any error that could be introduced by the InAmp.
          
			
          

		
			
	      

		
		
	
          
	
          
		
          
			
		
          
	
          
	
          
		
						
						
				
						
				
				
		
		
          
			
		
          
	
          

          

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