Highly Integrated Hard-Disk-Drive Motor Controller from STMicroelectronics Designed for Next-Generation Enterprise Drives

STMicroelectronics (NYSE: STM),a world leader in disk drive and system-on-chip solutions, today announced a hard-disk drive (HDD) motor-control chip intended for demanding enterprise-level HDD applications. The new L7220 controller integrates all of the circuits required to drive both the spindle motor and the voice-coil motor (VCM), plus the motor drive power FETs and multiple high-efficiency voltage regulators. It continues and complements ST’s HDD controller family, which includes the L7207 HDD controller for mobile and desktop drives.

ST is the market leader in enterprise HDD controllers. No other manufacturer offers such a high level of integration, enabling drive manufacturers to significantly reduce their bill of materials (BOM) and save space within the drive. Enterprise HDDs – typically used in server farms, workstations and high-performance desktop systems – are moving to Small Form Factor (SFF) sizes, where achieving a smaller PCB footprint is critical; the integration in the L7220 of the power FETs for both spindle and voice coil motors is a major contribution.

The new controller embeds four highly-efficient hysteretic positive switching regulators, and one -5V regulator, all with voltage margining. As well as eliminating the need for external regulators for the various voltages required by the drive, hysteretic control provides fast transient response and very high efficiency, increasingly important in server farms in particular, where reducing power consumption is a principal requirement.

In addition, the L7220 contains the latest version of ST’s respected Smooth Drive® pseudo-sinusoidal digital-drive technique for minimizing acoustic noise from the spindle motor, plus other circuits to limit spindle current, sense the start-up position and slow the spindle during power down.

The spindle-motor section power FETs are capable of delivering 3.0A peak current; ON-resistance is 0.3-ohms maximum at 125 degrees C. The VCM driver has 2.5A capability and 0.3-ohms maximum bridge impedance. It includes circuitry for discontinuous mode ramp unload at power off, with end of travel detection; an alternative voltage-mode power-off scheme; and a 15-bit linear DAC with gain switch, for current commands.

Evaluation samples of the L7220 are available now, and volume production in planned for mid-2008. The controller is priced at $15.00, in a 64-pin 10 x 10 x 1mm ePad package.

About STMicroelectronics
STMicroelectronics is a global leader in developing and delivering semiconductor solutions across the spectrum of microelectronics applications. An unrivalled combination of silicon and system expertise, manufacturing strength, Intellectual Property (IP) portfolio and strategic partners positions the Company at the forefront of System-on-Chip (SoC) technology and its products play a key role in enabling today’s convergence markets. The Company’s shares are traded on the New York Stock Exchange, on Euronext Paris and on the Milan Stock Exchange. In 2006, the Company’s net revenues were $9.85 billion and net earnings were $782 million. Further information on ST can be found at www.st.com.