BD7902CFS

Optical disc ICs

13/17

3) Reverse-rotation braking mode (spindle)

A reverse-rotation torque is applied when SPIN

< VC.

Reverse-rotation is detected with SPIN input and Hall input. If the spindle detects reverse rotation when SPIN

< VC,

all the outputs are shorted out to GND.

4) Short-circuit braking mode (spindle)

All the spindle driver outputs are shorted out to GND when SPIN

< VC.

2. Input/output timing chart

HU

+

HV

+

HW

+

SPIN

U

V

W

HU

−

HV

−

HW

−

Vref

SOURCE

Hi-Z

SINK

SOURCE

Hi-Z

SINK

SOURCE

Hi-Z

SINK

AB C D E F

G H

I

J K L

) Forward

rotation

mode

) Reverse

rotation

brake

) Reverse

protect

) Short

brake

FWD

FWD

FWD

REV