The LD-SPM-VCM-0001-050 Spindle/VCM megacell is a CMOS monolithic device that integrates spindle and VCM controllers as well as power stages into one megacell. The device operates from 3.3V or 5V power supply and is designed for a small-form-factor hard disk drive application.

A precision low voltage detection circuit monitors the power supply and initiates VCM retract at voltage fault condition. A 3-line serial port interface with read back capability provides interface to the microprocessor.

The spindle driver features a transconductance amplifier, current sense amplifier, power output drivers, sequencer, internal delay/masking logic, spindle brake circuit, FLL, and charge pump for locking the spindle to the programmed rotational speed.
The VCM driver features a transconductance amplifier, differential input current sense amplifier, ramp load/unload capability, and power output amplifier.

Features:

General features:

• Operates from single supply, 3.3V or 5V
• Precision low voltage monitor circuitry for the power supply
• Master Power on Reset
• Serial Port Interface with Read-back capability
• Over-temperature protection/warning
• Shock sensor signal processing
• Includes 1.8V, 2.5V, 3.3V regulators and a -3V (optional) regulator
• Low power consumption, 9mA in normal run mode

Spindle Driver:

• Commutator is driven by a FLL for high immunity to jitter
• Programmable 10-bit DAC
• Adjustable slew rate control
• External startup capability
• 1 A current capability with R_on = 1 W
  
• Digital commutation delay and blanking
  
• Programmable delay from Bemf zero crossing
  
• External INDEX signal for spin lock
  
• Active spindle braking capability
  

VCM Driver

• 0.4 Amp current capability with R_on = 1.5 W
  
• Programmable 14-bit DAC
  
• Ramp load/unload capability with 10-bit ADC
  
• Power-off retract with 9V charge-pump
  
• Programmable VCM current controlled by sense resistor