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4

CLC427 OPERATIONS

Description

The CLC427 contains two single supply voltage-feed-

back amplifiers. The CLC427 is a dual version of the

CLC423 with the following features:

• Operates from a single +5V supply

• Maintains near rail-to-rail performance

• Includes the negative rail (0V) in the Common

Mode Input Range (CMIR)

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

distortion

• Provides BW > 20MHz and 1MHz distortion

The CLC427 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

CLC427 is typically 0V to +3.7V. The typical output range

For simple single supply operation, it is recommended

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.

Standard 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

Single Supply Operation for Inputs that go below 0V

Figures 3 and 4 show possible non-inverting and invert-

ing 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 volt-

2.5V.

Figure 3: AC Coupled Non-inverting Configuration

Figure 4: AC Coupled Inverting Configuration

+

-

1/2

CLC427

0.1

µF

6.8

µF

+5V

3(5)

2(6)

4

8

1(7)

V

V

1

R

R

o

in

f

g

=+

+

+

-

1/2

CLC427

0.1

µF

6.8

µF

+5V

3(5)

2(6)

4

8

1(7)

V

V

R

R

o

in

f

g

=−

Select R to yield

desired R

R || R

t

in

tg

=

+

+

-

1/2

CLC427

0.1

µF

6.8

µF

+5V

R

3(5)

2(6)

4

8

1(7)

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

>>

+

-

1/2

CLC427

0.1

µF

6.8

µF

+5V

R

3(5)

2(6)

4

8

1(7)

R

+

VV

R

R

2.5

o

in

f

g

=−











 +

low frequency cutoff

1

2R C

gc

=

π

2.5V