3. Structure of the Photo Diode
1) Focus Error Signal (A+C)-(B+D)
This signal is generated in RF AMP IC (IC601 : AK8563) and controls the pick-up’s up and down to focus
on CD Disc.
2) Tracking Error Signal (DPP Method) {(A+D)-(B+C)}-
k
X {(E-F)+(G-H)}
This signal is generated in RF AMP IC (IC601 : AK8563) and controls the pick-up’s left and right shift to
find the track on CD Disc.
3) RF Signal (A+B+C+D)
This signal is converted to DATA signal in DSP IC (IC501 : CXD3011R-1)
21
H
G
F
E
D
C
B
A
Pick-Up module
Photo Diode
Tracking
Focusing
Infrared Iaser
Pick-Up module
Photo Diode
Tracking
Focusing
Infrared Iaser