LG LH-W7501TA Service Manual page 40

9. SPINDLE CONTROL WAVEFORMS (NO DISC CONDITION)
10. TRACKING CONTROL RELATED SIGNAL(System checking)
FIG 9-1
FIG 10-1(DVD)
3-17
DMSO(1.4V/1.8V)
(IC501 PIN 18)
SP-(3.6V/2.4V)
(IC404 PIN 18)
SP+(3.6V/4.8V)
(IC404 PIN 17)
TE(IC401 PIN 39)
TRSO(IC501 PIN 13)
T-(IC404 PIN 16)
T+(IC404 PIN 15)