SMOOTH DRIVE

™ SYSTEM

1.8A DRIVE PEAK CAPABILITY

SLEW RATE CONTROL

INDUCTIVE SENSE START-UP ROUTINE

THERMAL SHUTDOWN

SUITABLE FOR 5V AND 12V APPLICATION

ONLY ONE HALL SENSOR IS REQUIRED

DESCRIPTION

The L7203 SPINDLE MOTOR IC includes a three

phase brushless spindle motor controller and the

power stage in switching mode. The device is de-

signed for both 5V and 12V OPTICAL DRIVE ap-

plication requiring up to 1.8A peak of current.

The device is realized in BCD5, a 0.7

µm Mixed

technology.

The spindle motor position detection is carried

out by means of a single comparator with hyster-

esis. In the start-up phase the "inductive sense

start up method" is used to detect the rotor posi-

tion, determining the direction of starting rotation.

This procedure is implemented by a logic circuit

on chip.

The device applies three sinusoidal voltages to

the motor coils.

This is obtained through the application of the

April 2001

LOW VOLTAGE

DETECTOR

PRS

SRC

AGND

DGND

BLOCK DIAGRAM

ORDERING NUMBERS: L7203 (SO20)

L7203S (SSO24)

L7203

SMOOTH DRIVE SPINDLE MOTOR FOR OPTICAL DRIVE

APPLICATION WITH POWER INTEGRATED

®

SO20

SSO24

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