KBMF

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4. CROSSTALK BEHAVIOR

The crosstalk phenomena is due to the coupling between 2 lines. The coupling factor (

β12 or β21 )

increases when the gap across lines decreases, this is the reason why we provide crosstalk

measurements for monolithic device to guarantee negligeable crosstalk between the lines. In the example

line 2. This phenomenon has to be taken into account when the drivers impose fast digital data or high

frequency analog signals in the disturbing line. The perturbed line will be more affected if it works with low

voltage signal or high load impedance (few k

Ω).

Figure 8 gives the measurement circuit for the analog crosstalk application. In figure 9, the curve shows

the effect of the Data line on the CLK line. In usual frequency range of analog signals (up to 100MHz) the

effect on disturbed line is less than -37dB.

Figure 7: Crosstalk phenomena

Figure 8: Analog Crosstalk measurements

configuration

Figure

9:

Typical

Analog Crosstalk meas-

urement

Line 1

Line 2

DRIVERS

RECEIVERS

αβ

1G1

12G2

V+

V

αβ

2G2

21G1

V+

V

50

Ω

RF IN

Vg

50

TEST BOARD

1

10

100

1,000

-120

-100

-80

-60

-40

-20

0

F (MHz)

crosstalk (dB)