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HMC788A Recommended for New Designs
The HMC788A is a 0.01 GHz to 10 GHz, gain block, monolithic microwave integrated circuit (MMIC) amplifier using gallium arsenide (GaAs), pseudomorphic...
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HMC788A on Analog.com

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HMC788A damaged

		
	
				

			

									
					    jerry_12345
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on Jun 5, 2021 
				
			
			
		

		
		                     
				
        		

		    
		    		    
		    			

			    
Hello, I found a problem when using HMC788A .
























Six pieces of hmc788a share a 5v power supply generated by TPS7A91. Each HMC788A  is biased via a TCCH-80 (minicircuits).

















The problem is that some amplifiers would draw a high current (about 400mA) and get damaged . This happens randomly.












What are the possible reasons for this??

			

			
									    

			        
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[edited by: jerry_12345 at 2:02 AM (GMT -4) on 6 Jun 2021]
				

						
		                             
                        

    

                                            
                 hmc788a
                
                                                    
                 amplifiers
                
                                                    
                 Gain Blocks
                
                                                    
                 rf amplifiers
                
                                
            

    
    
		


				
				        
        		

			
						
									
												
			
			
                        
                                    
                        
                                                    
                        
            
			            
						
						
			
			
			
			
		


        
        
        
    
					

			





















	

	

					



			


				
	









	
    
	

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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on Jun 23, 2021 7:43 PM
            
            
						
			            		
    
		
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    Hi Jerry,
    

    I am not familiar with the TPS7A91 LDO but I'm curious as to why you are using the TCCH-80 as a bias inductor. Depending on how you are using the HMC788A (frequency range, at saturation, etc.) it's right up against some of that inductors limitations and it's value is off. We recommend using the 6.35μH Piconics conical choke (P/N: CC75T38K240G5). 
    

    Thanks,
    

    DanO
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
						
				
				
				
		
		
    
			
		
    
	
    

    

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                on Sep 21, 2021 1:55 PM
            
            
						
			            		
    
		
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    Dan,
    

    

    We're seeing the same issue and we are using a 6.7 uH conical inductors from Piconics. We see the same sort of thing. The current draw shoots up and the amp dies. It still passes a signal through it but there is no amplification.
    

    It seems to happen at random. We currently have a system that uses 16 of these amps on 8 RF channels. We've had 4 channels blow in he last hour.
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
				
				
				
		
		
    
			
		
    
	
    

    

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