7

LT1311

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-

tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Basic Optical System Focus and Tracking Signal Generation

Wide Common-Mode Range Instrumentation Amplifier

–IN

1

7

3

5

12

14

8

10

OUT

1131 TA03

100k

+IN

100k

R2

2k

R2

′

2k

TRIM

FOR CMRR

20k

1

2

3

4

5

6

7

14

13

12

10

9

8

2k

2k

1311 TA04

10V

TRACKING

SIGNAL

(A + B) – (C + D)

FOCUS

SIGNAL

(A + C) – (B + D)

WORST-CASE OUTPUT DRIFT IS 120

µV/°C

BANDWIDTH IS 7MHz

0.1% SETTLING IS LESS THAN 250ns

11

–

+

–

+

5V

IN A

IN B

BIAS

IN C

IN D

OUT A

OUT B

OUT C

10V

OUT D

LT1311

0.1

µF

2k

8pF

2k

2k

2k

2k

2k

2k

5V

8pF

–

+

1/2 LT1215

–

+

1/2 LT1215

2k

2k

2k