ISL54222A_10 Datasheet, PDF (8/19 Pages) Intersil Corporation – High-Speed USB 2.0 (480Mbps) Multiplexer

ISL54222A
Test Circuits and Waveforms (Continued)
V_DD
C
V_DD
C
IMPEDANCE
ANALYZER
HSDxx
SEL
0V OR
Dx
V_DD
GND ^OE
Repeat test for all switches.
FIGURE 4. CAPACITANCE TEST CIRCUIT
SIGNAL
GENERATOR
HSD1x
Dx
50Ω
SEL
V_IN
ANALYZER
Dx
HSD2x
NC
GND OE
R_L
Signal direction through switch is reversed, worst case values
are recorded. Repeat test for all switches.
FIGURE 5. CROSSTALK TEST CIRCUIT
V_{DD C}
t_ri
DIN+
DIN-
OUT+
OUT-
10%
90%
50%
t_{skew_i}
90% _50%
10%
t_fi
t_ro
90%
10%
90%
50%
t_{skew_o}
50%
t_f0
10%
V_IN
DIN+
DIN-
15.8Ω
143Ω
15.8Ω
143Ω
SEL
COMD2
COMD1
D2
D1
OE
OUT+
C_L
45Ω
OUT-
C_L
45Ω
GND
|tro - tri| Delay Due to Switch for Rising Input and Rising Output Signals.
|tfo - tfi| Delay Due to Switch for Falling Input and Falling Output Signals.
|tskew_0| Change in Skew through the Switch for Output Signals.
|tskew_i| Change in Skew through the Switch for Input Signals.
FIGURE 6A. MEASUREMENT POINTS
FIGURE 6. SKEW TEST
FIGURE 6B. TEST CIRCUIT
8
FN6902.1
February 4, 2010