LD7015
SPINDLE/VCM COMBO CHIP
Revision 1.5 Page 1
SPINDLE/VCM SPECIFICATION
1. DESCRIPTION
LD7015 is a CMOS monolithic device that integrates spindle and VCM controllers as well as power stages into one
chip. The device operates from 3.3V power supply. LD7015 is designed for a small-form-factor hard disk drive
applications.
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.
2. FEATURES
2.1. General
• Operates from single supply, 3.3V
• Small footprint 64-Pin TQFP package or Flip Chip
• 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
• On-chip 1.8V, 2.5V and -3V Regulators
• Low power consumption, 9mA in normal run mode
2.2. Spindle Driver
• Commutator is driven by a FLL for high immunity to jitter
• Programmable 10-bit DAC
• Adjustable slew rate control
• External startup capability
• 0.4 Amp current capability with R
on
= 1.4 Ω
• Digital commutation delay and blanking
• Programmable delay from Bemf zero crossing
• External INDEX signal for spin lock
• Active spindle braking capability
2.3. VCM Driver
• 0.4 Amp current capability with Ron = 2.2 Ω
• Programmable 14-bit DAC
• Ramp load/unload capability with 10-bit ADC
• Programmable VCM current controlled by sense resistor