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CXA1372BQ/BS

Notes on Operation

1. Connection of the power supply pin

2. FSET pin

The FSET pin determines the cut-off frequency fc for the focus and tracking high-frequency phase compensation.

3. ISET pin

ISET current = 1.27V/R

= Focus search current

= Tracking jump current

= 1/2 sled kick current

5. FE (focus error) and TE (tracking error) gain changing method

(1) High gain: Resistance between FE pins (Pins 5 and 6) 100k

Ω → Large

Resistance between TA pins (Pins 11 and 12) 100k

Ω → Large

(2) Low gain: A signal, whose resistance is divided, is input to FE and TE.

6. Input voltage of microcomputer interface Pins 20 to 25, should be set as follows.

× 90% or more

× 10% or less

7. Focus OK circuit

(1) Refer to the "Description of Operation" for the time constant setting of the focus OK amplifier LPF and the

mirror amplifier HPF.

(2) The equivalent circuit of FOK output pin is as follows.

20k

50k

100k

DGND

FOK

DGND

33

FOK comparator output is:

≈ near Vcc

dual ±5V power supplies

+5V

0V

VC

+5V

–5V

0V

single 5V power supplies

Vcc

VC

FE

TE