AN1139 STMicroelectronics, AN1139 Datasheet - Page 11

• Manufacturer Part Number: AN1139
• Description: L6254 - L6268 - L6269 12V DISK DRIVE POWER COMBO IC
• Manufacturer: STMicroelectronics

AN1139 APPLICATION NOTE
retract.The bit will return to normal when the temperature will drop about 60 C.
All the functions of
the device but the reading in the serial port, will be in stand-by as long as this bit is set to 0.
THERMAL_WARN - Bit #1. Normally is set to 1, when the Junction temperature reaches about 125 C,
the bit will be set to 0. The device will take no action upon this bit set to 0. Corrections are demanded
to the P. This bit will return automatically to normal (=1) when the temperature will drop below the set
point (about 125 C).
ROTOR_STUCK - Bit #2. Normally is set to 1, if the Spindle BEMF is not detected, the bit will be set to
0. This can happen for example during Start-Up because the Spindle motor may be Stucked.
The device will tristate the Spindle and VCM outputs upon this bit is set to 0.
FAULT - Bit #3. Normally is set to 0, if the Spindle motor decelerate rapidly or the FCOM signal change
to high frequency, the bit will be set to 1. The device will take no action upon this bit set to 0. Corrections
are demanded to the P.
MASK_TIME - Bit #4. By reading continuosly this bit, the internal BEMF mask time signal can be
monitored. When the bit is 0, the BEMF is masked.
ERROR_LOCK - Bit #5. When the Spindle speed is at target speed +/- 16 S sample, the bit will be set
to 1, otherwise will be set to 0.
ALIGN - Bit #6. Normally is set to 1, when the Spindle motor is in the ALIGN phase of the internal
Align&GO start-up, the bit will be set to 0.
GO - Bit #7. Normally is set to 1, when the Spindle motor is in the GO phase of the internal Align&GO
start-up, the bit will be set to 0.
By reading and decoding the Identification register, the revision of the Device can be retrieved.
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