The Hard Drive Controller

The 100GB Momentus 7200.1 hard drive uses what appears to be a custom-made hard drive controller from STMicroelectronics.

We couldn't find out anything about this controller, even after searching through STMicroelectronics' website. But this hard drive controller should not differ much from others in its job of managing the transfer of data between the drive and the host.

The Motor Drive Controller

Seagate used a motor drive controller from STMicroelectronics. Again, this appears to be a custom chip, made specifically for Seagate.

The main advantage of using this chip is ST's proprietary Smooth Drive pseudo-sinusoidal digital drive technology. Smooth Drive allows the hard drive to minimize torque ripple to reach a higher track density as well as reduce acoustic noise.

The Cache Buffer

The 100GB Momentus 7200.1 comes with 8MB of buffer memory, courtesy of a single 54-pin TSOP II SDRAM chip from Samsung.

The Samsung K4S641632H-UC60 is a 64Mbit SDRAM chip rated at 60ns. It has a maximum bandwidth of 333MB/s at the rated clock speed of 166MHz.

Breather Hole

Like all other hard drives, the 100GB Momentus 7200.1 comes with a breather hole. In this case, it's on the top plate.

The breather hole allows condensation inside the hard drive to escape as well as equalizes the hard drive's internal pressure with the ambient pressure. So, please make sure you do not occlude the hole when you install the hard drive!

Jumpers And Connectors

At the end of the PCB are the PATA interface and jumper block (from left to right).

Since most notebooks only have a single hard drive bay, there's usually no need to change it from the default setting of Master (no jumper installed).