Method and apparatus for an active read/write head

Abstract

A method and apparatus for collocating an interface circuit with a disk drive read/write head is described. In one embodiment the interface circuit is attached to the load arm on one side and the miniflex interconnect on the other. The read/write head is mounted on the miniflex directly below the interface circuit. The interface circuit comprises a read signal preamplifier, a write driver, and head selection circuitry. A common multiplexer circuit is used to perform the other conventional read/write circuit functions. The common multiplexer circuit includes a head selection block to determine which heads are activated, a head driver block, and a read receiver block. The common multiplexer circuit is mounted at the base of the miniflex.

We claim:  
     
         1 . A disk drive head-arm assembly comprising: 
 a head;    an interface circuit, said interface circuit having a first and a second side, wherein said interface circuit preamplifies signals from said head;    a load arm, said load arm coupled to said first side of said interface circuit;    an interconnect, said interconnect having a first and a second side, said first side of said interconnect coupled to said second side of said interface circuit. Said second side of said interconnect coupled to said head;    wherein said interface circuit couples said preamplified signals from said head to said interconnect.    
     
     
         2 . The apparatus of  claim 1  wherein said head comprises a magnetoresistive head.  
     
     
         3 . The apparatus of  claim 2  wherein said interface circuit is bump soldered to said interconnect.  
     
     
         4 . The apparatus of  claim 3  wherein said interface circuit comprises: 
 a substrate;  
 an integrated circuit formed on said substrate; said substrate is a backgrinded substrate.  
 
     
     
         5 . The apparatus of  claim 4  wherein said interface circuit further comprises: 
 a read signal preamplifier; and  
 a write current driver.  
 
     
     
         6 . A disk drive head-arm assembly comprising: 
 a head;    a load arm;    an interconnect, said interconnect having a first and a second side, said first side of said interconnect, said second side of said interface circuit coupled to said head;    wherein said interface circuit preamplifies signals from said head, and couples said preamplified signals from said head to said interconnect.    
     
     
         7 . The apparatus of claims  6  wherein said head is a notched head.  
     
     
         8 . The apparatus of  claim 7  wherein said head comprises a magnetoresistive head.  
     
     
         9 . The apparatus of claims  8  wherein said interface circuit is bump soldered to said interconnect.  
     
     
         10 . The apparatus of  claim 9  wherein said interface circuit comprises: 
 a substrate;  
 an integrated circuit formed on said substrate;  
 said substrate is a backgrinded substrate.  
 
     
     
         11 . The apparatus of  claim 10  wherein said interface circuit further comprises: 
 a read signal preamplifier; and  
 a write current driver.  
 
     
     
         12 . a method of forming a head-arm assembly comprising an interface circuit, and interconnect, a load arm, and a head, said method comprising the steps of: 
 coupling a first side of said interface circuit to said load arm;    coupling a second side of said interface circuit to a first side of said interconnect;    coupling a second side of said interconnect to said head.    
     
     
         13 . The method of  claim 12  wherein said step of coupling a second side of said interface circuit to a first side of said interconnect further comprises bump soldering said second side of said interface circuit to said first side of said interconnect.  
     
     
         14 . The method of  claim 13  wherein said step of bump soldering said second side of said interface circuit to said first side of said interconnect further comprises backgrinding said interface circuit after said interface circuit is bump soldered.  
     
     
         15 . A method of forming a head-arm assembly comprising an interface circuit, an interconnect, a load arm, and a head, said method comprising the steps of: 
 coupling a first side of said interconnect to said load arm;    coupling a second side of said interconnect to a first side of said interface circuit;    coupling a second side of said interface circuit to said head.    
     
     
         16 . The method of  claim 15  wherein said step of coupling a second side of said interconnect to a first side of said interface circuit further comprises bump soldering said second side of said interconnect to said first side of said interface circuit.  
     
     
         17 . The method of  claim 16  wherein said step of bump soldering said second side of said interconnect to said first side of interface circuit further comprises backgrinding said interface circuit after said interface circuit is bump soldered.