LG HT552TH Service Manual page 45

9. SPINDLE CONTROL WAVEFORMS (NO DISC CONDITION)
10. TRACKING CONTROL RELATED SIGNAL(System checking)
FIG 9-1
FIG 10-1(DVD)
3-18
SPINO(1.4V/1.8V)
(IC501 PIN 207)
SP-(3.6V/2.4V)
(IC501 PIN 192)
SP+(3.6V/4.8V)
(IC501 PIN 191)
CD_DVDCT(IC501 PIN 169)
TRO(IC501 PIN 210)
TR-(IC401 PIN 12)
TR+(IC401 PIN 11)