For replacing the circuit boards on the hard disk drive, just simple unscrew PCB and swap won’t help any more! My WD hard drive PCB’s chip has fried. I have already purchased a donor PCB to try to salvage the drive; however, there was no life breathed into it. The hard drive still didn’t spin…
The goal of this post is to show you how a hard drive Printed Circuit Board(PCB) built. What are its main parts, how do they look and what are these parts names and abbreviations. As an example we are going to disassemble 3.5″ SATA drive.
To make it more fun we going to tear to pieces pretty new 1TB Seagate ST31000333AS hard drive. Let’s take a look on our “Guinea pig”.
Hard Drive PCB Main Parts:
The fancy piece of green woven glass and copper with SATA and power connectors called Printed Circuit Board(PCB). PCB holds on place and wires electronic components of HDD.
Now let’s remove PCB and see electronic components on the other side.
Hard Drive PCB Parts:
The heart of PCB is the biggest chip in the middle called Micro Controller Unit(MCU). On modern HDDs MCU usually consists of Central Processor Unit or CPU which makes all calculations and Read/Write channel – special unit which converts analog signals from heads into digital information during read process and encodes digital information into analog signals when drive needs to write. MCU also has IO ports to control everything on PCB and transmit data through SATA interface.
The Memory chip is DDR SDRAM memory type chip. Size of the memory defines size of the cache of HDD. This PCB has Samsung 32MB DDR memory chip which theoretically means HDD has 32MB cache (and you can find such information in data sheet on this HDD) but it’s not quite true. Because memory logically divided on buffer or cache memory and firmware memory. CPU eats some memory to store some firmware modules and as far as we know only Hitachi/IBM drives show real cache size in data sheets for the other drives you can just guess how big is the real cache size.
Next chip is Voice Coil Motor controller(VCM controller). This fellow is the most power consumption chip on PCB. It controls spindle motor rotation and heads movements. The core of VCM controller can stand working temperature of 100C/212F.
Flash chip stores part of the drive’s firmware. When you apply power on a drive, MCU chip reads content of the flash chip into the memory and starts the code. Without such code drive wouldn’t even spin up. Sometimes there is no flash chip on PCB that means content of the flash located inside MCU.
Shock sensor can detect excessive shock applied on a drive and send signal to VCM controller. VCM controller immediately parks heads and sometimes spins down the drive. It theoretically should protect the driver from further damage but practically it doesn’t, so don’t drop you drive – it wouldn’t survive. On some drives shock sensors used for detection even light vibrations and signals from such sensors help VCM controller tune up heads movements. Such drives should have at least two shock sensors.
Another protection device called Transient Voltage Suppression diode(TVS diode). It protects PCB from power surges from external power supply. When TVS diode detects power surge it fries itself and creates short circuit between power connector and ground. There are two TVS diodes on this PCB for 5V and 12V protection.
Tips: Hard Drive Failures cased by PCB can be solved by replacing a new one. How to find a matching pcb please refer to: How to find a Matching PCB
Recovery data from dead hard drives which do note that disassembling a hard drive is not recommended and can result to permanent data loss and further damage to your drive. If your data is business critical, please seek professional help.
The green board on the bottom of the hard drive is known as Hard Drive Printed Circuit Board (HDD PCB). The main function of the PCB is to supply power to the hard drive, maintain speed and rotation of the spindle, and control all internal operations through its firmware. Essentially, PCB is the brains of the hard drive that all components are heavily dependent upon. Hard drives that do not spin up after the power has been supplied can be diagnosed as PCB failure.
First, we should find the matching PCB:
Western Digital – same board number which is etched on the PCB, begin with 2060-
Seagate – same board number which is etched on the PCB, begin with 100…; If you can’t find the number on the PCB(Old Models), you should find the same Main Controller IC
Maxtor – same Main Controller IC
Hitachi – same information on the small white label.
Samsung – same board number which is etched on the PCB, begin with BF41-
Remove the PCB from both hard drives with star screwdriver. Replace the fautly PCB with replacement one. If you HDD spins up, but can’t be recognized, you should also exchange the BIOS on the PCB.
You should know the hard drive failures are not always caused by PCB failure. Swap PCB can not guaranteed to fix your hard drive.
Article by HDDZone.com – Second hand hard disk drive PCB supplier!
There are lots of data recovery companies in the world. They have the best data recovery softwares, excellent engineers, first-class cleanroom, etc. However, these companies are difficult to become the top data recovery companies like Ontrack, CBL, SalvageData, etc.
Most data recovery companies can exactly diagnose problems of the Hard Disk Drives. And definitely know how to get the data back. Sometimes the problems can be easily resolved by replacing the damaged parts, like exchange the damaged heads, exchange the damaged PCB, repair the firmware, etc. Sometimes the companies can’t finish the easy operations. Because they don’t have the matching HDD accessories in hand.
If you also encountered these problems, please don’t worry now. We can offer all of the matching HDD accessories which you want. You just need to contact us and issue your detailed requirements. We can send your required HDD accessories with best price to you in short time.
Excellent working condition PCB Logic Boards:
Maxtor, Western Digital, Seagate, IBM, Samsung, Fujitsu, Hitachi, Quantum and many more Manufacturers.
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