Hitachi Global Storage Technologies has introduced two fourth-generation hard drives for automotive applications, the Endurastar J4K50 and N4K50, with respective operating temperature ranges of -30 to 85°C (-22 to 185 °F) and -16 to 70 °C (3 to 158 °F) and altitude ranges of -300 to 5,000 meters and -300 to 3,000 meters. Both drives are available in 30 GB, 40 GB and 50 GB capacities, with an 8 MB segmented cache buffer, and both can survive up to 3.0 G operating vibration and up to an 800 G drop shock.
Shinjiro Iwata, chief marketing officer, said OEMs tend to prefer the J4K50 while aftermarket equipment suppliers prefer the N4K50. Both drives use Thermal Fly-height control technology to maintain an appropriate distance between the read/write head and the disk surface despite extreme temperature variances. fluid dynamic bearing motors are tuned to help the disks start up at low temperatures and achieve high temperature operating endurance; high-capacity breather filters inside the drive are said to improve absorption capability over standard filters to protect from excessive humidity and organic pollutants, and shock sensors monitor environmental disturbances to maintain data integrity during on-the-go write operations.
"We see a tremendous opportunity for all kinds of useful and entertaining digital data populating automotive hard drives that will make them an invaluable component of the modern car," Iwata said. International Data Corporation predicts that automotive hard drives will grow at a 38% compound annual rate between 2005 and 2010.