Fo rc e -S e n s e S w it c h e s
_________________________________Te s t Circ u it s /Tim in g Dia g ra m s (c o n t in u e d )
V+
V+
VL
VL
0V
VL
V
IN_
V
IN
IN_
NO_ OR NC_
50Ω
MAX4554
MAX4555
MAX4556
COM_
V-
V
OUT
V
OUT
∆V
OUT
GND
EN
C
L
1000pF
∆V IS THE MEASURED VOLTAGE DUE TO CHARGE TRANSFER
OUT
V-
ERROR Q WHEN THE CHANNEL TURNS OFF.
Q = ∆V x C
OUT
L
V- IS CONNECTED TO GND (0V) FOR SINGLE-SUPPLY OPERATION.
Figure 13. Charge Injection
V+
V+
VL
VL
NO_
MAX4554
MAX4555
MAX4556
VL
NC_
1MHz
CAPACITANCE
ANALYZER
ADDRESS
SELECT
COM_
V-
IN_
EN
GND
/MAX456
V-
Figure 14. COM_, NO_, NC_ Capacitance
V+
V+
VL
VL
10nF
10nF
NETWORK
ANALYZER
VOUT
VIN
V
IN
OFF ISOLATION = 20 log
COM_
50Ω
50Ω
MAX4554
MAX4555
MAX4556
NO_, NC_
GND
V-
VOUT
VIN
VL
ON LOSS = 20 log
V
OUT
MEAS.
REF
VOUT
VIN
IN_
ADDRESS
SELECT
CROSSTALK = 20 log
EN
50Ω
50Ω
10nF
V-
MEASUREMENTS ARE STANDARDIZED AGAINST SHORT AT SOCKET TERMINALS. OFF ISOLATION IS MEASURED BETWEEN COM_ AND "OFF" NO_ OR NC_ TERMINALS.
ON LOSS IS MEASURED BETWEEN COM_ AND "ON" NO_ OR NC_ TERMINALS. CROSSTALK IS MEASURED BETWEEN COM_ TERMINALS WITH ALL SWITCHES ON.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED. V- IS CONNECTED TO GND (0V) FOR SINGLE-SUPPLY OPERATION.
Figure 15. Frequency Response, Off-Isolation, and Crosstalk
26 ______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
