AND8054/D

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8

C1

C2

C4

R2

R4

A3

A2

A1

R1

R3

Figure 10. Absolute Oscillator Signal Flow Diagrams

A3 +*

R4

R3

A2 +*

1

sR2C2

A2 +*

1

sR2C2

A1 +*

1

sR1C1

A1 +*

1

sR1C1

A3 +*

R4

R3

1

sR4C4 ) 1

+

–

+

–

+

–

ABSOLUTE OSCILLATOR DESIGN EQUATIONS

Step 1: Find LG and

Ds

The loop gain is found by breaking the loop and inserting a “test’’ voltage into the input.

A1 + –

1

sR1C1

A2 + –

1

sR2C2

A3 + –

R4

R3

LG

+

VOUT

VTEST

+ A1

A2

A3

Ds +

N(s)

D(s)

+ 1 * LG + 1 * –

1

sR1C1

–

1

sR2C2

–

R4

R3

+ 1 )

R4

s2R1R2R3C1C2

+ s2 )

R4

R1R2R3C1C2

+

s2R1R2R3C1C2 ) R4

s2R1R2R3C1C2

N(s)

+ s2R1R2R3C1C2 ) R4