bility compared to a SOT23 diode when subjected to IEC
1000-4-2 8kV contact discharge. A performance summary
is shown in Figure 2.
ANTENNA VARISTOR S21
0
ESD TEST OF ANTENNAGUARD RATINGS
Breakdown Voltage (Vb) — 0402 & 0603 3pF Ratings
-5
VC04AG183R0
VC06AG183R0
VC06AG18120
520
70
0603 - 12pF
500
480
60
50
Breakdown Voltage (Vb) — 0603 12pF Rating
-10
0603 - 3pF
460
440
420
400
40
30
20
10
dB
-15
-20
-25
-30
0.01
0.1
Frequency (GHz)
1.0
10
0402 - 3pF
380
0
100
1000
8kV ESD Strikes
0
10,000
Figure 5. Attenuation vs Frequency
Figure 2. Repetitive 8kV ESD Strike
Antenna varistors also turn on and divert ESD overvoltages
at a much faster rate than SOT23 devices (typically 300pS
vs 1500pS - 5000pS). See Figure 3.
PEAK
100%
90%
30ns
Typical implementations of the antenna varistors are shown
for use in cell phone, pager and wireless LAN applications in
Figures 6A, 6B and 6C.
SITVS TURN ON TIME
1.5nS to 5nS
FET
2.2pF
2.7pF
Figure 6A. Cell Phone
60ns
1ns
MLV CALCULATED
TURN ON TIME
300pS to 700pS
30ns
60ns
TIME (ns)
Figure 3. Turn On Time
The equivalent circuit model for a typical antenna varistor is
shown in Figure 4.
12pF
L
n
L
n
= 100V INDUCTANCE
R
V
C
1
R
I
C
1
= DEVICE CAPACITANCE
R
V
= VOLTAGE VARIABLE RESISTOR
R
I
= INSULATION RESISTANCE
Figure 4. Antenna Varistor
Figure 6B. Pager
The varistor shown exhibits a capacitance of
≤3pF
which
can be used to replace the parallel capacitance typically
found prior to the antenna output of an RF amplifier. In the
off state, the varistor acts as a capacitor and helps to filter
RF output. The varistor is not affected by RF output power
or voltage and has little insertion loss. See Figure 5.
FET
3pF
Varistor
29
TransGuard
PACKAGING
•
Chips
•
Axial Leads
®
49
TransGuard
®
AVX Multilayer Ceramic Transient Voltage Suppressors
Packaging - Chips / Embossed Carrier Configuration 8mm Tape Only
8mm Embossed Tape
Metric Dimensions Will Govern
CONSTANT DIMENSIONS
Tape Size
8mm
D
0
E
P
0
P
2
2.0 ± 0.05
(0.079 ± 0.002)
T Max.
0.600
(0.024)
T
1
0.10
(0.004)
Max.
G
1
0.75
(0.030)
Min.
See Note 3
G
2
0.75
(0.030)
Min.
See Note 4
+0.10
8.4
-0.0
1.75 ± 0.10
4.0 ± 0.10
+0.004
(0.059
-0.0
) (0.069 ± 0.004) (0.157 ± 0.004)
VARIABLE DIMENSIONS
Tape Size
B
1
Max.
See Note 6
4.55
(0.179)
D
1
Min.
See Note 5
1.0
(0.039)
F
P
1
R
Min.
See Note 2
25
(0.984)
T
2
W
A
0
B
0
K
0
8mm
3.5 ± 0.05
4.0 ± 0.10
(0.138 ± 0.002) (0.157 ± 0.004)
+0.3
2.5 Max. 8.0
-0.1
+.012
(0.098) (0.315
-0.004
) See Note 1
NOTES:
1. A
0
, B
0
, and K
0
are determined by the max. dimensions to the ends of the terminals extending from the component body and/or the body dimensions of the component.
The clearance between the end of the terminals or body of the component to the sides and depth of the cavity (A
0
, B
0
, and K
0
) must be within 0.05 mm (0.002) min. and
0.50 mm (0.020) max. The clearance allowed must also prevent rotation of the component within the cavity of not more than 20 degrees (see sketches C & D).
2. Tape with components shall pass around radius “R” without damage.
3. G
1
dimension is the flat area from the edge of the sprocket hole to either the outward deformation of the carrier tape between the embossed cavities or to the edge of
the cavity whichever is less.
4. G
2
dimension is the flat area from the edge of the carrier tape opposite the sprocket holes to either the outward deformation of the carrier tape between the embossed
cavity or to the edge of the cavity whichever is less.
5. The embossment hole location shall be measured from the sprocket hole controlling the location of the embossment. Dimensions of embossment location and hole
location shall be applied independent of each other.
6. B
1
dimension is a reference dimension for tape feeder clearance only.
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