The AT78C7015 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. The AT78C7015 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, a 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.