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The THLD signal is generated on the LA9230M, 9240M, 9250M Series side, and causes the tracking error signal to
be held during the JP pulse period.
* The tracking brake
The relationship between the TES, HFL, and TOFF signals during the track jump period c is as shown below. The
TOFF signal is generated from the HFL signal with the changing edge of the TES signal. The high of the HFL signal
is for the mirrored area, while the low is for the pitted area. As the beam sweeps from the mirrored surface to the
pitted area, TOFF becomes high, and as the beam sweeps from the pitted area to the mirrored surface, TOFF is made
low in the gain-enhanced state (TGL low), and the brake is applied.
TES (when moving towards the outside)
TES (when moving towards the inside)
TOFF output
• JP 3-state Output
Code
$B6
JP 3-state output
$B7
JP 2-state output (conventional method)
Using the JP 3-state command, the track jump can be controlled with a single pin, however, the gain must be
increased on the servo side because the kick gain will decrease by 6 dB.
2-state output
3-state output
• Track check mode
Code
$F0
Track check IN
$F8
Track check OUT
$FF
Two byte command reset
After the track check IN or track check OUT command has been entered, then when a discretionary number between
8 and 254 is entered as binary data, a track count of the specified number + 1 will be performed.
Command
Track check
HFL
COMMAND
COMMAND
The number of desired track checks = the number of track checks input + 1
Track check
Binary input of the desired
In/Out command
number of tracks +1
LC78626KE
RES = low
High impedance output
RES = low
Double byte
command reset
Goes low when the track
Rising edge at the
check is complete.
number of tracks/2
Brake command
No. 5995-18/34
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