MAX4989
USB 2.0 Hi-Speed 2-of-4 Crosspoint Switch
4 _______________________________________________________________________________________
Test Circuits/Timing Diagrams
IN, OUT, AND OFF DEPEND ON SWITCH CONFIGURATION.
MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
OFF-ISOLATION IS MEASURED BETWEEN IN AND OFF TERMINAL ON EACH SWITCH.
ON-LOSS IS MEASURED BETWEEN IN AND OUT TERMINAL ON EACH SWITCH.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO THE OTHER CHANNEL.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.
V
OUT
C_
OFF
IN
OUT
V
IN
MAX4989
OFF-ISOLATION = 20log
V
OUT
V
IN
ON-LOSS = 20log
V
OUT
V
IN
CROSSTALK = 20log
V
OUT
V
IN
NETWORK
ANALYZER
50Ω
50Ω 50Ω
50Ω
MEAS REF
0V OR V
CC
50Ω
Figure 1. On-Loss, Off-Isolation, and Crosstalk
t
r
< 5ns
t
f
< 5ns
50%
V
IL
LOGIC
INPUT
R
L
OUT
C_
C
L
INCLUDES FIXTURE AND STRAY CAPACITANCE.
V
OUT
= V
IN (
R
L
)
R
L
+ R
ON
V
N_
V
IH
t
OFF
0V
IN
0.9 x V
0UT
0.9 x V
OUT
t
ON
V
OUT
SWITCH
OUTPUT
LOGIC
INPUT
IN AND OUT DEPEND ON SWITCH CONFIGURATION.
C
L
V
OUT
MAX4989
