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CXA2596M

Description of Functions

RF Amplifier

Each signal current from the photodiodes A, B, C and D is I-V converted, and input to Pins 5, 6, 7 and 8.

These signals are added by the RF summing amplifier and equalized by the RF equalizing amplifier and then

output to Pin 16. When the RF signal is equalized, an equalizing circuit is added to Pin 15.

Focus Error Amplifier

The operation of (B+D)–(A+C) is performed and the signal is output to Pin 14.

I-V

A

A

24k

I-V

B

B

24k

I-V

C

C

24k

I-V

D

D

24k

GND

14k

4.2k

VC

4.3k

5k

RF SUMMING AMP

5.7k

VC

25.4k

RF EQAMP

RFOUT

RFE

RFO

5

6

7

8

15

16

GND

VC

FEOUT

FE

I-V

A

A

I-V

B

B

I-V

C

C

I-V

D

D

23.3k

23.3k

23.3k

23.3k

87k

25p

87k

25p

FOCUS

ERROR AMP

14

5

6

7

8