CMRR over frequency can be achieved through the

placement of an RC network between the outputs (A and

B) of the two amplifiers of the CLC412.

Non-Inverting Current-Feedback Integrator.

The circuit of Figure 7 achieves its high-speed integration

by placing one of the CLC412's amplifiers in the feedback

loop of the second amplifier configured as shown.

Figure 7

Low-Noise Wide-Bandwidth Transimpedance

Amplifier. Figure 8 implements a low-noise

transimpedance amplifier using both channels of the

CLC412. This circuit takes advantage of the lower input-

bias-current noise of the non-inverting input and achieves

negative feedback through the second CLC412 channel.

Figure 8

Buffered 2nd-Order Sallen-Key Low-Pass Filter.

Figure 9 shows one implementation of a 2nd order

Sallen-Key low pass filter buffered by one of the CLC412's

channels. The CLC412 enables greater precision since

it provides the advantage of very low output impedance

and very linear phase throughout the pass-band.

½CLC412

½CLC412

R

2

1

+

+

-

-

V

in

3

Figure 4

½CLC412

½CLC412

RR

++

--

Figure 6

R

R

½CLC412

½CLC412

Differential Line Receiver. Figures 5 and 5a show two

different implementations of an instrumentation amplifier

which convert differential signals to single-ended. Figure

Figure 5

Figure 5a

High-Speed Instrumentation Amplifier.

For applications requiring higher CMRR the composite

circuit of Figure 6 uses the two amplifiers of the CLC412

to create balanced inputs for the CLC420 voltage-

feedback op amp. The DC CMRR can be fine tuned

CLC420

½CLC412

½CLC412

2

1

R

1

2

1

1

=

A

B

+

+

+

-

-

-

½CLC412

½CLC412

R

C

+

+

+

-

-

VV

R

R

sRC

oin

=

2

1

A

R

R

f

g

2

2

2

=−

V

IR

R

Z(s

A

s

o

sf

T

p

p

=

+

+

F

H

GG

GG

I

K

JJ

JJ

1

1

2

)

ω

ω

½CLC412

½CLC412

+

+

-

-

Figure 9

½CLC412

½CLC412

+

-

+

-

R

V

V

K

RR C C

ss

RC

R C

K

RC

R R C C

out

in

o

=

++

+

−

















+

12

1

2

2

11

2

2

9

22

1 2

1

2

11

1

1

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