LC78622NE
• CLV three-value output
MSB
LSB
0
Command
RES = low
1
0
0
1
1
1
1
0
0
1
1
0
0
CLV THREE VALUE OUTPUT
CLV TWO VALUE OUTPUT
(the scheme used by previous products)
●
1
1
The CLV three-value output command allows the CLV to be controlled by a single pin.
• Internal brake modes
MSB
LSB
1
Command
RES = low
1
1
1
1
1
1
1
1
1
0
1
1
1
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
0
0
0
1
1
0
0
1
1
1
0
0
INTERNAL BRAKE ON
0
INTERNAL BRAKE OFF
●
1
INTERNAL BRAKE CONTROL
INTERNAL BRAKE CONTINUOUS MODE
RESET CONTINUOUS MODE
TON MODE DURING INTERNAL BRAKING
RESET TON MODE
1
0
●
●
1
0
— Issuing the internal brake-on (C5H) command sets the LC78622NE to internal brake mode. In this mode, the
disk deceleration state can be monitored from the WRQ pin when a brake command (06H) is executed.
— In this mode the disk deceleration state is determined by counting the EFM signal density in a single frame, and
–
when the EFM signal count falls under four, the CLV pin is dropped to low. At the same time the WRQ signal,
which functions as a brake completion monitor, goes high. When the microprocessor detects a high level on the
WRQ signal, it should issue a STOP command to fully stop the disk. In internal brake continuous mode (CBH),
–
the CLV pin high-level output braking operation continues even after the WRQ brake completion monitor
goes high.
Note that if errors occur in deceleration state determination due to noise in the EFM signal, the problem may be
rectified by changing the EFM signal count from four to eight with the internal brake control command (A3H).
— In TOFF output disabled mode (CDH), the TOFF pin is held low during internal brake operations. We
recommend using this feature, since it is effective at preventing incorrect detection at the disk mirror surface.
No. 6015-12/31