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4

CLC423 OPERATIONS

Description

The CLC423 is a voltage feedback amplifier designed for

single supply operation. The CLC423 is a single version

of the CLC427 with the following features:

s

Operates from a single +5V supply

s

Maintains near rail-to-rail performance

s

Includes the negative rail (0V) in the Common

Mode Input Range (CMIR)

s

Offers low -74/-94dBc 2nd and 3rd harmonic

distortion

s

Provides BW > 20MHz and 1MHz distortion

The CLC423 is designed to operate from 0 and 5V

supplies. The specifications given in the

Electrical

Characteristics table are measured with a common

which the inputs are applied and the output voltages are

specified.

Operating from a single +5V supply, the CMIR of the

CLC423 is typically 0V to +3.7V. The typical output range

For DC coupled single supply operation, it is recom-

mended that input signal levels remain above ground.

For input signals that drop below ground, AC coupling

and level shifting the signal are possible remedies.

For input signals that remain above ground, no

adjustments need to be made. The non-inverting and

inverting configurations for both input conditions are

illustrated in the following 2 sections.

DC Coupled Single Supply Operation

Figures 1 and 2 show the recommended non-inverting

and inverting configurations for purely positive input

signals.

Figure 1: Non-inverting Configuration

Figure 2: Inverting Configuration

AC Coupled Single Supply Operation

Figures 3 and 4 show possible non-inverting and

inverting configurations for input signals that go below

ground. The input is AC coupled to prevent the need

for level shifting the input signal at the source.

The

resistive voltage divider biases the non-inverting input to

Figure 3: AC Coupled Non-inverting Configuration

Figure 4: AC Coupled Inverting Configuration

+

-

CLC423

0.1

µF

6.8

µF

+5V

3

2

4

7

6

V

V

1

R

R

o

in

f

g

=+

+

CLC423

3

2

7

6

+

-

0.1

µF

6.8

µF

+5V

4

V

V

R

R

o

in

f

g

=−

Select R to yield

desired R

R || R

t

in

tg

=

+

3

2

7

6

CLC423

+

-

0.1

µF

6.8

µF

+5V

R

4

C

R

+

VV

1

R

R

2.5

o

in

f

g

=+











 +

low frequency cutoff

1

2R C

, where: R

R

2

in

c

in

==

π

2.5V

>>

RC

RC

gc

>>

CLC423

3

2

7

6

+

-

0.1

µF

6.8

µF

+5V

R

4

R

+

VV

R

R

2.5

o

in

f

g

=−











 +

low frequency cutoff

1

2R C

gc

=

π

2.5V