USBUFxxW6
Technical information
Figure 10. Figure 10: Analog crosstalk
measurements
Figure 11. Typical analog crosstalk
results
Analog crosstalk (dB)
0
TEST BOARD
-20
-40
50Ω
50Ω
UUx
Vg
-60
-80
-100
1
10
100
Frequency (MHz)
1,000
gives the measurement circuit for the analog crosstalk application. In
the curve shows the effect of the D+ cell on the D-cell. In usual frequency range of analog
signals (up to 100 MHz) the effect on disturbed line is less than -37 db.
Figure 12. Digital crosstalk measurements configuration
+5V
74HC04
3.3 V
+5V
74HC04
D+
D1
Rt
Ct
Rp
D4
Square
Pulse
Generator
V
G1
+5V
D-
D2
Gnd
Rt
Ct
D3
3.3 V
β
21
V
G1
shows the measurement circuit used to quantify the crosstalk effect in a classical
digital application.
Figure 13. Digital crosstalk results
V
G1
β
21
V
G1
shows, with a signal from 0 to 5 V and rise time of few ns, the impact on the
disturbed line is less than 250 mV peak to peak. No data disturbance was noted on the
other line.The measurements performed with falling edges gives an impact within the same
range.
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