Possible configurations

AN2995

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Doc ID 15840 Rev 1

3

Possible configurations

This chapter provides instructions on how to set-up the board with several typical

configurations.

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Figure 3: low-pass Sallen-Key configuration

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Figure 4: high-pass Sallen-Key configuration

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Figure 5: differential amplifier configuration

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Figure 6: in-loop compensation configuration

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Figure 7: out-of-loop compensation configuration

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Figure 8: AC-coupled configuration

You can also connect several boards together if you need to evaluate more complicated

schematics using several operational amplifiers.

3.1

Low-pass Sallen-Key configuration

The low-pass Sallen-Key configuration is a second-order filter configuration. Z4 and Z9 are

used to set the gain.

Fc = 1/(2*PI*sqrt(Z1*Z2*C5*C6))

Z7, Z8, Z12 and Z14 must be "not connected". Z3 and Z13 must be shorted.

Figure 3.

Low-pass Sallen-Key configuration

3.2

High-pass Sallen-Key configuration

Like the low-pass Sallen Key configuration, this is also a second-order filter configuration.

Z4 and Z9 are used to set the gain.

Fc = 1/(2*PI*sqrt(C1*C2*Z5*Z6))

Z7, Z8, Z12 and Z14 must be "not connected". Z3 and Z13 must be shorted.

Vout

Vin1

Z9

Z5

Z2

Z1

Z6

Z4

AM04502