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AD7864 Production
The AD7864 is a high speed, low power, 4-channel, simulta-neous sampling 12-bit analog-to-digital converter (ADC) that operates from a single 5 V supply...
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AD7864 on Analog.com

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AD7864 Vdrive VDD

		
	
				

			

									
					    parziwal
					
							

            
            			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Nov 21, 2023 
				
			
			
		
    
		
		                     
				
        		
    
		    
		    		    
    
		      		            		            		    
    Product Number:  AD7864 
    
    		        		    		    
    
		    		    
		    			
    
			    
    Hi, 
    

    

    I would like to know what should DVDD values be when interfacing with 3.3V MCU. 
    

    When interfacing with 3.3V MCU should Vdrive = 3.3V and DVDD be 5V. 
    

    And what are the VOL , VOH , VIL , VIH values when Vdrive = 3.3V  and VDD =5V
    

    

    Is there any other signal other than the following effected by Vdrive value?
    

    CONVST, BUSY,EOC,FRSTDATA,RD,CS,H/S,SEL[SL1-SL4] and DATA
    

    

    Basically, we are worried if there is a level translator needed when interfacing the ADC with 3.3V FPGA.
    

    

    Thanking you 
    

    With best regards
    
			
    
			
									
		                             
                        

    
    
                                            
                 ad7864
                
                                                    
                 Simultaneous Sampling A/D Converters
                
                                                    
                 Precision A/D Converters
                
                                
            
    
    
    
		
    

				
				        
        		
    
			
						
									
												
			
			
                        
                                    
                        
                        
                        
            
			            
						
						
			
			
			
			
		
    

        
        
        
    
					
    
			
    


    
















    
	
    
	
    
					



			


				
	









	
      
	

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      •  Analog Employees  
      •  Super User  
      
            
						
                            
            
            				
            
                on Nov 22, 2023 2:34 AM
            
            
						
			            		
      
		
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      Hi,
      

      You can check the Absolute Maximum Rating which displays the maximum values that the ADC can handle as well as the sequence of the power supply. The DVDD input value should be rated at 5V +- 5% regardless of the Vdrive value. The Vdrive pin provides the positive supply voltage for the output drivers and this will follow your logic level. When interfacing an MCU with a logic level of 3.3V, the condition of the input of the ADC should be Vdrive= 3.3V and DVDD= 5V. The DVDD is the one supplying the digital section of the ADC it doesn't affect the logic level of the digital communication.
      

      Regards,
      

      Andrei 
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
						
						
				
				
		
		
      
			
		
      
	
      

      

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                on Nov 23, 2023 7:36 AM
            
            
												
						in reply to andreialejandro
					
										
			            		
        
		
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        Hi, 
        

        Thank you for the information. 
        

        Could you please let me know what values for VOL , VOH , VIL , VIH values when Vdrive = 3.3V  and VDD =5V.
        

        

        Thanking you 
        

        With best regards 
        
			
        

		
			
	      

		
		
	
        
	
        
		
        
			
		
        
	
        
	
        
		
						
						
						
						
				
				
		
		
        
			
		
        
	
        

        

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