L7200

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Power On Reset (POR) circuitry is included. Upon detection of a low voltage condition, POR is asserted, the

internal registers are reset, and spindle power circuitry is tri-stated. The BEMF is rectified providing power for

actuator retraction followed by dynamic spindle braking. Three Linear regulators and a Shock Sensor circuitry

are also integrated.

The device is built in BCD mixed signal technology allowing dense digital/analog circuitry to be combined with

a high power DMOS output stage.

BLOCK DIAGRAM

CHARGE

PUMP

SUPPLY

FAULT

MONITORS

REFERENCE

VOLTAGE VCC/4

& GAIN SWITCH

14 BIT

VCM DAC

A=4

SUPPLY

OUT_A

OUT_B

RSENSE

OUT_C

VCM_A+

VCC

VCM_A-

SENSE_IN-

SENSE_IN+

VCM_GND

CTAP

PUMP

SDATA

SCLK

SDEN

TR_12V

TR_5V

ISENSE

TR_3.3V

8V

Regulator

2.5V

Regulator

3.3V

Regulator

VREG8_DRV

VREG3.3_IN

VREG2.5_IN

VREG8_IN

SHOCK

DETECTOR

SPINDLE

Architecture

FLL &

DIGITAL

FILTER

BIPOLAR /

TRIPHASE

BEMF

DETECTION

VCM

PSM/LIN

BEMF

RECTIFICATION

VCM

CALIBRATION

THERMAL

INDUCTIVE

SENSE

START-UP

RE-SYNC

PWM C

ISOFET

PWM B

PWM A

VCC

SERIAL

PORT

REGISTERS

DYNAMIC/

REVERSE

BRAKE

RAMP LOADING

DESCRIPTION (continued)