Tubular Pi Type
Capacitors
Spectrum Control Technology Inc. Pi (π) type capacitors
are ideally suited for connector and filter block applica-
tions requiring high capacitance values. Compared to
feed-thru capacitors, the Pi capacitors have a much
narrower transition band between the pass band and
stop bands. Pi filters are effective in stopping high
frequency interference without affecting necessary
frequencies immediately below the stop band.
Our Pi capacitors consist of a unique tubular capacitor
with an inner electrode imbedded within the ceramic
material. This is in contrast to a solid tube capacitor
whose inner electrode is on the inside diameter of the
tube. Our embedded electrode Pi capacitor design
offers several distinct advantages over other ceramic
capacitors.
s
Solid
Electrode "E
1
"
Ground "G"
Electrode "E
2
"
Versatility in Capacitance Values and Voltage
Ratings.
The placement of the imbedded electrode
can be chosen to optimize capacitor performance.
Dimensional Constancy.
The imbedded electrode
makes it possible to change electrical performance
without altering the inner or outer diameter of the
ceramic tube for a given terminal size.
High Mechanical Strength.
In order to achieve
increased capacitance in a plain tubular capacitor,
manufacturers must utilize a thin wall tube. This
decrease in wall thickness often leads to an increase
in process problems. Spectrum's imbedded electrode
permits the use of a thicker tubular wall, allowing for
increased yields and minimal process problems in
the assembly of connectors.
s
Embedded
Electrode Tube
Electrode "E
1
"
Ground "G"
s
Electrode "E
2
"
Buried electrode tube
Features
s
s
s
s
s
s
s
s
Effectively stops high frequency interference
Miniature size - high ratio of capacitance to volume
Low inductance, non-polar
Ideal for multi-pin connector applications
Pi filter - includes a ferrite inductor
Impervious to moisture and contamination
Excellent reliability
-55°C to +125°C operation
Insertion Loss
Insertion Loss (db)
80
33000
70
60
10000
50
40
30
20
10
4000
1000
310
100
1 MHz
10 MHz
Frequency
100 MHz
1GHz
Typical Pi Filter Performance*
34
SPECTRUM CONTROL INC.
• 8031 Avonia Rd. • Fairview, PA 16415 • Phone: 814-835-1650 • Fax: 814-835-1651 • Web site: www.spectrumcontrol.com
SPECTRUM CONTROL GmbH
• Hansastrasse 6 • 91126 Schwabach, Germany • Phone: (49)-9122-795-0 • Fax: (49)-9122-795-58
Ferrite I.D.
.030
(0.76)
min. (2 places)
Specifications
50/100/200 VDCW + 125°C
.080
(2.03)
max.
C
1
C
2
Pi (
π
) Section
C
1
+ C
2
= C
TOTAL
L
±.010
(0.25)
O.D.
I.D.
Dimensions
Ferrite
Part
Number
51-109-008
51-109-009
51-109-010
51-134-001
51-134-002
51-134-003
51-107-007
51-107-008
51-107-009
VDCW
at
125°C
200
100
50
200
100
50
200
100
50
Cap.
Value
GMV
(µF)
10,000
.026
12,000
15,000
12,000
.045
15,000
22,000
15,000
.068
22,000
30,000
(17.3)
± .004
(± .10)
.135
(3.43)
± .004
(± .10)
.104
(2.64)
± .004
(± .10)
(1.14)
± .003
(± .08)
.098
(2.49)
± .003
(± .08)
.073
(1.85)
± .003
(± .08)
.445
(11.30)
(0.66)
± .002
(± .05)
.082
(2.08)
.057
(1.45)
± .003
(± .08)
.425
(10.80)
Tube
I.D.
Tol.
O.D.
Tol.
I.D.
Tol.
L
Minimum Insertion Loss (db)
300
MHz
to
1
3
10
30
100
10
MHz MHz MHz MHz MHz GHz
—
5
7
5
7
10
8
10
12
11
13
14
13
14
16
15
16
18
20
23
28
20
25
32
25
32
35
48
50
55
48
52
57
52
57
60
65
65
70
68
70
70
70
70
70
70
70
70
70
70
70
70
70
70
Notes:
1. Dimensions are in inches, dimensions shown in
( )
are in millimeters.
2. Capacitance value (C
1
plus C
2
) is maximum available capacitance in GMV tolerance.
3. Other dimensional variations and capacitance values are available. Consult factory.
SPECTRUM CONTROL INC.
• 8031 Avonia Rd. • Fairview, PA 16415 • Phone: 814-835-1650 • Fax: 814-835-1651 • Web site: www.spectrumcontrol.com
SPECTRUM CONTROL GmbH
• Hansastrasse 6 • 91126 Schwabach, Germany • Phone: (49)-9122-795-0 • Fax: (49)-9122-795-58
35