AN3394

Doc ID 018754 Rev 5

23/29

Appendix A

A.1

Equivalent circuit

Figure 22.

Final equivalent circuit

1.

Equation (A.I.1)

2.

Equation (A.I.2)

3.

Resonance pulsation:

conditions are:

Equation (A.I.3)

R

eq

R

RXP

R

PA

×

R

RXP

R

PA

+

--------------------------------

=

Z

tot

1

jC

11

ω

×

×

---------------------------

R

eq

1L

PA

ω

2

C

22

C

+

(

×

×

–

() j ω L

PA

×

×

+

×

R

C

22

ω

2

×

×

–

() j ω L

PA

×

×

+

------------------------------------------------------------------------------------------------------------------------------

×

=

Z

tot

R

tot

jX

tot

×

+

=

R

tot

R

out

=

and

X

tot

0

=

R

tot

R

eq

L

PA

C

11

ω

2

1L

PA

ω

2

×

C

22

C

11

+

()

–

ω

2

L

PA

R

eq

×

×

C

11

×

1L

PA

ω

2

C

22

×

×

–

()

×

+

()

×

×

×

×

–

R

eq

C

11

ω

×

×

()

2

1L

PA

C

22

ω

2

×

×

–

()

2

ω

2

L

PA

C

11

×

×

()

2

+

×

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

=