CLC1606 datasheet(13/18 Pages) CADEKA

13 / 18 page

Data Sheet

www.cadeka.com

Application Information

Basic Operation

Figures 3, 4, and 5 illustrate typical circuit configurations for

non-inverting, inverting, and unity gain topologies for dual

supply applications. They show the recommended bypass

capacitor values and overall closed loop gain equations.

Figure 3. Typical Non-Inverting Gain Circuit

Figure 4. Typical Inverting Gain Circuit

Figure 5. Typical Unity Gain (G=1) Circuit

CFB amplifiers can be used in unity gain configurations.

Do not use the traditional voltage follower circuit, where

the output is tied directly to the inverting input. With a

CFB amplifier, a feedback resistor of appropriate value

must be used to prevent unstable behavior. Refer to fig-

ure 5 and Table 1. Although this seems cumbersome, it

does allow a degree of freedom to adjust the passband

characteristics.

Feedback Resistor Selection

One of the key design considerations when using a CFB

amplifier is the selection of the feedback resistor, Rf. Rf is

used in conjunction with Rg to set the gain in the tradi-

tional non-inverting and inverting circuit configurations.

Refer to figures 3 and 4. As discussed in the Current Feed-

back Technology section, the value of the feedback resis-

tor has a pronounced effect on the frequency response of

the circuit.

Table 1, provides recommended Rf and associated Rg val-

ues for various gain settings. These values produce the

optimum frequency response, maximum bandwidth with

minimum peaking. Adjust these values to optimize perfor-

mance for a specific application. The typical performance

characteristics section includes plots that illustrate how

the bandwidth is directly affected by the value of Rf at

various gain settings.

Gain

(V/V

Rf (Ω)

Rg (Ω)

±0.1dB BW

(MHz)

-3dB BW

(MHz)

390

136

1300

270

150

1200

270

67.5

115

750

Table 1: Recommended Rf vs. Gain

In general, lowering the value of Rf from the recom-

mended value will extend the bandwidth at the expense

of additional high frequency gain peaking. This will cause

increased overshoot and ringing in the pulse response

characteristics. Reducing Rf too much will eventually

cause oscillatory behavior.

Increasing the value of Rf will lower the bandwidth. Low-

ering the bandwidth creates a flatter frequency response

and improves 0.1dB bandwidth performance. This is im-

portant in applications such as video. Further increase in

Rf will cause premature gain rolloff and adversely affect

gain flatness.

0.1μF

6.8μF

Output

G = - (Rf/Rg)

For optimum input offset

voltage set R1 = Rf || Rg

Input

+Vs

-Vs

0.1μF

6.8μF

0.1μF

6.8μF

Output

G = 1

Rf is required for CFB amplifiers

Input

+Vs

-Vs

0.1μF

6.8μF

0.1μF

6.8μF

Output

G = 1 + (Rf/Rg)

Input

+Vs

-Vs

0.1μF

6.8μF

CLC1606 데이터시트(PDF) 13 Page - Cadeka Microcircuits LLC.

CLC1606 데이터시트(HTML) 13 Page - Cadeka Microcircuits LLC.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

데이터시트 다운로드

링크 URL