CERAMIC CHIP CAPACITORS
Table 1 – EIA Temperature Characteristic
INTRODUCTION
Codes for Class I Dielectrics
Significant Figure
of Temperature
Coefficient
Multiplier Applied
to Temperature
Coefficient
Tolerance of
Temperature
Coefficient
Ceramic chips consist of formulated ceramic
dielectric materials which have been fabricated into thin
layers, interspersed with metal electrodes alternately
exposed on opposite edges of the laminated structure.
The entire structure is then fired at high temperature to
produce a monolithic block which provides high capaci-
tance values in a small physical volume. After firing, con-
ductive terminations are applied to opposite ends of the
chip to make contact with the exposed electrodes.
Standard end terminations use a nickel barrier layer and
a tin overplate to provide excellent solderability for the
customer.
KEMET multilayer ceramic chip capacitors are
produced in plants designed specifically for chip capa-
citor manufacture. The process features a high degree
of mechanization as well as precise controls over raw
materials and process conditions. Manufacturing is
supplemented by extensive Technology, Engineering
and Quality Assurance programs.
KEMET ceramic chip capacitors are offered in the
five most popular temperature characteristics. These
are designated by the Electronics Industies Association
(EIA) as the ultra-stable C0G (also known as NP0,
military version BP), the stable X7R (military BX or
BR), the stable X5R, and the general purpose Z5U and
Y5V. A wide range of sizes are available. KEMET multi-
layer ceramic chip capacitors are available in KEMET's
tape and reel packaging, compatible with automatic
placement equipment. Bulk cassette packaging is also
available (0805,0603 and 0402 only) for those pick and
place machines requiring its use.
PPM per
Degree C
Letter
Symbol
Multi-
plier
Number
Symbol
PPM per
Degree C
Letter
Symbol
0.0
0.3
0.9
1.0
1.5
C
B
A
M
P
-1
0
1
2
3
4
30
G
H
J
K
L
-10
60
-100
-1000
-10000
120
250
500
KEMET supplies the C0G characteristic.
For Class II and III dielectrics (including X7R,
X5R, Z5U & Y5V), the first symbol indicates the
lower limit of the operating temperature range, the
second indicates the upper limit of the operating
temperature range, and the third indicates the
maximum capacitance change allowed over the
operating temperature range. EIA type designa-
tion codes for Class II and III dielectrics are
shown in Table 2.
Table 2 – EIA Temperature Characteristic Codes for
Class II & III Dielectrics
Low Temperature
Rating
High Temperature
Rating
Maximum Capacitance
Shift
Degree
Letter
Symbol
Degree
Celsius
Number
Symbol
Letter
Symbol
EIA
Celsius
Percent
Class
+10C
-30C
-55C
Z
Y
X
+45C
+65C
2
4
5
6
7
8
9
1.0%
1.5%
A
B
C
D
E
F
P
R
S
T
U
V
II
II
+85C
2.2%
II
+105C
+125C
+150C
+200C
3.3%
II
4.7%
II
7.5%
II
10.0%
II
15.0%
II
22.0%
III
III
III
III
+ 22/-33%
+22/-56%
+22/-82%
KEMET supplies the X7R, X5R, Z5U and Y5V characteristics.
3. Capacitance Tolerance:
See tables on pages 73-76.
ELECTRICAL CHARACTERISTICS
4.
Capacitance:
Within specified tolerance when measured per
Table 3.
1.
Working Voltage:
Refers to the maximum continuous DC working
voltage permissible across the entire operating
temperature range. The reliability of multilayer
ceramic capacitors is not extremely sensitive to
voltage, and brief applications of voltage above
rated will not result in immediate failure. However,
reliability will be degraded by sustained exposure
to voltages above rated.
The standard unit of capacitance is the farad.
For practical capacitors, capacitance is usually
expressed in microfarads (10 -6 farad), nanofarads
-9
-12
(10 farad), or picofarads (10 farad). Standard
measurement conditions are listed in Table 3 -
Specified Electrical Limits.
Like all other practical capacitors, multilayer
ceramic capacitors also have resistance and
inductance. A simplified schematic for the single
frequency equivalent circuit is shown in Figure 1.
At high frequency more complex models apply -
see KEMET SPICE models at www.kemet.com for
details.
2.
Temperature Characteristics:
Within the EIA classifications, various tempera-
ture characteristics are identified by a three-symbol
code; for example: C0G, X7R, X5R, Z5U and Y5V.
For Class I temperature compensating
dielectrics (includes C0G), the first symbol desig-
nates the significant figures of the temperature
coefficient in PPM per degree Celsius, the second
designates the multiplier to be applied, and the
third designates the tolerance in PPM per
degrees Celsius. EIA temperature characteristic
codes for Class I dielectrics are shown in Table 1.
67
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