L6245

The L6245 contains in a single chip all the functions to operate a sensorless brushless (DC) motor  and a voice coil motor, suitable for hard disk drive applications.

The L6245 is configured to interface directly to an 8 bit parallel microprocessor bus, and has a register based architecture to reduce number of interconnection lines. All the positioning loop for sensorless spindle is integrated, including BEMF sensing, digital masking, digital delay and sequencing. All timing function are performed digitally, thus no external filtering components are required.

 The VCM driver is a transconductance amplifier, able to provide 2 different current ranges, suitable for seeking or tracking of the head actuator. When a low voltage is detected, a monitor, in sequence, resets the internal registers, puts in tristate the spindle powers, retracts the actuator, and applies the dynamic brake of the spindle.

The L6245 is realized in Multipower-BCD 2 technology, which combine isolate DMOS power transistors with CMOS and Bipolar circuits in the same monolithic layer, and is assembled in a 64-pin PQFP.