5

Monolithic Auto-Zeroed Operational Amplifers

TC911A

TC911B

© 2001 Microchip Technology Inc.

DS21481A

+

–

TC911

18 k

Ω

6.4 k

Ω

3.6 k

Ω

6.4V

4

6

7

3

2

0.1

µF

+15V

V

= 10V

OUT

TYPICAL APPLICATIONS

Thermometer Circuit

10-Volt Precision Reference

+9V

TC911

REF02

–

+

VOUT

R

2

R

3

R

1

ADJ

TEMP

OUT

V

REF

V

= V

OUT

1 + R

2

[

(

REF

–

] [

R

2

]

1 + R

2

[

R + R

1

1

(

)]

d (V

)

d V

OUT

=

≈K (2.1 mV/°C)

K = 1 +

R

2

dT

R X R

TEMP

TEMP

3

3

dT

R + R

1

3

R

1

1

R X R

3

1

R X R

3

Programmable Gain Amplifier With Input Multiplexer

+

–

IN1

TC911

IN2

IN3

A1 A2 A3 A4WR

+5V

–5V

GND

+5V –5V

+5V

–5V

1

VOUT

2 k

Ω

18 k

Ω

INPUT

CHANNEL

SELECT

68HC11

GAIN

SELECT

A1 A2 A3 A4

WR

LATCH

GND

10

X

100

1000

XX

X

99 k

Ω

999 k

Ω

1 k

Ω

1 k

Ω

IN4

IC1b

IC1b

IC1a, b, = Quad Analog Switch