L6243

L6243D

VOICE COIL MOTOR DRIVER

12V/5V OPERATION

PARKING FUNCTION

FOR HARD

DISK

HEAD ACTUATOR

OUTPUT CURRENT UP TO 2A DC, 2.5A

PEAK

LOW SATURATION VOLTAGE

LOGIC AND POWER SUPPLY MONITOR

LINEAR CONTROL

THERMAL PROTECTION

ENABLE FUNCTION

CURRENT SENSE RESISTOR CONNEC-

TIONS

DESCRIPTION

The L6243/D is a Bipolar IC developed for use in

Hard Disk Head Actuator positioning applications.

The Power Op-Amp Output Bridge, Differential

Amplifier, and Error Amplifier, are controlled by

TTL/CMOS, input compatible, Digital Logic, and

an Analog Current Control Voltage. A simple

RC compensation network, tied to the output of

the Error Amp, will configure the system to work

as a Transconductance Amplifier to drive a

Voice Coil Motor in Linear Mode.

Additional features include Power On Reset De-

lay, Enable and Park, as well as a general pur-

pose Operational Amplifier. A logic low at the

Park input activates the parking function. Holding

the Enable input low will disable the device by

forcing the outputs into a tristate mode. Power

Fail Monitors for the logic and power supplies in-

itiate an automatic parking sequence during a

power failure. A resistor programmed parking

voltage enables a constant velocity head retract.

This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.

July 1996

BLOCK DIAGRAM

PLCC44

SO(24+2+2)

ORDERING NUMBERS:

L6243

L6243D

1/12