For seagate hdd recovery maybe you need a matching donor pcb. Here is a list of Seagate Barracuda PCB rescource for your reference from HDDZone.com.
These files are in PDF, if you can not open them you can download a tool by click here:
Seagate Barracuda 7200.9 Circuit Boards
Seagate Barracuda 7200.10 Circuit Boards
Seagate Barracuda 7200.11 Circuit Boards
Seagate Barracuda 7200.12 Circuit Boards
HTML Sources:
Seagate Barracuda 7200.12 PCB
Seagate Barracuda 7200.11 PCB
Seagate Barracuda 7200.10 PCB
Seagate Barracuda 7200.9 PCB
Seagate Barracuda 7200.8 PCB
Seagate Barracuda 7200.7 PCB
If you are from a small recovery company you can download them on you computer for you hdd repair or data recovery needs.