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SCDS174B − AUGUST 2004 – REVISED MAY 2005
V
+
V
COM
COM
Capacitance
Meter
V
= V or GND
+
BIAS
V
NC
NO
NC
V = V or V
I
IH IL
V
NO
Capacitance is measured at NC,
NO, COM, and IN inputs during
ON and OFF conditions.
V
BIAS
IN
V
I
GND
Figure 14. Capacitance (C , C
, C
, C
, C
, C
)
I
COM(ON) NC(OFF) NO(OFF) NC(ON) NO(ON)
V
+
TEST
R
L
C
L
V
COM
V
NC
or V
NC or NO
NC or NO
NO
t
50 Ω
50 Ω
35 pF
35 pF
V
ON
+
+
COM
IN
V
COM
(2)
C
L
R
L
t
V
OFF
V
I
V
0
Logic
Input
(V )
I
+
(2)
C
R
L
50%
50%
L
Logic
(1)
GND
Input
t
t
OFF
ON
Switch
Output
90%
90%
(V
NC
orV )
NO
(1)
(2)
All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, Z = 50 Ω, t < 5 ns, t < 5 ns.
O
r
f
C
L
includes probe and jig capacitance.
Figure 15. Turn-On (t ) and Turn-Off Time (t
)
ON
OFF
V
+
V
Logic
Input
(V )
I
+
V
NC
orV
NO
50%
NC or NO
NC or NO
0
V
COM
COM
Switch
Output
90%
t
90%
(2)
C
R
L
L
(V
)
COM
IN
V
I
BBM
Logic
(1)
V
or V = V /2
NO +
= 50 Ω
= 35 pF
NC
GND
Input
R
C
L
L
(1)
(2)
All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, Z = 50 Ω, t < 5 ns, t < 5 ns.
L
O
r
f
C
includes probe and jig capacitance.
Figure 16. Break-Before-Make Time (t
)
BBM
16
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