L6268 Datasheet, PDF (1/17 Pages) STMicroelectronics – 12V DISK DRIVE SPINDLE & VCM, POWER & CONTROL “COMBO”

®
L6268
12V DISK DRIVE SPINDLE & VCM, POWER
& CONTROL “COMBO”
PRODUCT PREVIEW
GENERAL
12V (+/- 10%) OPERATION.
REGISTER BASED ARCHITECTURE
MINIMUM EXTERNAL COMPONENTS
BICMOS + VERTICAL DMOS (1.5mm)
BICMOS TECHNOLOGY
VCM DRIVER
1.5A DRIVE CAPABILITY
0.9W TOTAL BRIDGE IMPEDANCE AT 25°C
LINEAR MODE
PHASE SHIFT MODULATION (PWM MODE)
INSTANTANEOUS, (GLICH FREE) SWITCH
BETWEEN THE 2 MODES
CLASS AB OUTPUT DRIVERS
ZERO CROSSOVER DISTORSION
14 BIT DAC DEFINE OUTPUT CURRENT
SELECTABLE TRANSCONDUCTANCE
4 PROGRAMMABLE PARKING VOLTAGE
DYNAMIC BRAKE
SPINDLE DRIVER
2.0A DRIVE CAPABILITY
0.8W TOTAL BRIDGE IMPEDANCE AT 25°C
BEMF, INTERNAL OR EXTERNAL, PROC-
ESSING
SENSOR-LESS MOTOR COMMUTATION
PROGRAMMABLE COMMUTATION PHASE
DELAY
LINEAR MODE AND CONSTANT TOFF PWM
OPERATION MODE
INTERNAL FREQUENCY LOCKED LOOP
SPEED CONTROL (FLL)
BEMF RECTIFICATION DURING RETRACT
BUILT-IN ALIGNAMENT&GO START-UP
INDUCTIVE SENSING START UP OPTION
RESYNCHRONIZATION
DYNAMIC & REVERSE BRAKE
CONTROLLABLE OUTPUT SLEW RATE
OTHER FUNCTIONS
12V AND 5V MONITORING WITH EXTERNAL
SET TRIP POINTS AND HYSTERESIS
POWER UP/DOWN SEQUENCING
TQFP44 (10x10mm with slug)
ORDERING NUMBER: L6268
LOW VOLTAGE SENSE
3.3V INPUT LOGIC COMPATIBILITY
THERMAL SHUTDOWN AND PRETHERMAL
WARNING
DESCRIPTION
The L6268 integrates into a single chip both spin-
dle and VCM controllers as well as power stages.
The device is designed for 12V disk drive applica-
tion requiring up to 2.0A of spindle and 1.5A of
VCM peak currents.
A serial port with up to 25 MHz capability provides
easy interface to the microprocessor. A register
controlled Frequency Locked Loop (FLL) allows
flexibility in setting the spindle speed. Integrated
BEMF processing, digital masking, digital delay,
and sequencing minimize the number of external
components required.
Power On Reset (POR) circuitry is included. Upon
detection of a low voltage condition, POR is as-
serted, the internal registers are reset, and spin-
dle power circuitry is tri-stated. The BEMF is recti-
fied providing power for actuator retraction
followed by dynamic spindle braking.
The device is built in BICMOS technology allow-
ing dense digital/analog circuitry to be combined
with a high power DMOS output stage.
April 1999
This is preliminary information on a new product now in development. Details are subject to change without notice.
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