1、 EIA STANDARD Ceramic Dielectric Capacitors Classes I, II, III and IV Part I: Characteristics and Requirements EIA-198-1-F (Revision of EIA-198-1-E) NOVEMBER 2002 ELECTRONIC COMPONENTS, ASSEMBLIES EIA-198-B-1: EIA-198-B-2; EIA-198-B-3A and EIA-198-C, EIA-198-D, and EIA-198-E have been incorporated i
2、nto EIA-198-F. EIA-198-1-F vi This page left blank. EIA-198-1-F Page 1 EIA-198-1-F of this standard provides means to characterize ceramic capacitors electrically and mechanically by use of type designators. In addition, this section outlines dielectric classifications, marking specifications and te
3、st sequences. 1.1 Dielectric classification There are four major classifications of ceramic dielectrics, with class I being the least variable with temperature and voltage, and class IV being the most variable. Class I dielectrics are typically used in applications requiring the tightest tolerance.
4、1.1.1 Class I Components of this type are temperature compensating ceramic dielectrics, fixed capacitors of a type suited for resonant circuit applications or other applications where high Q and stability of capacitance characteristics are required. (See table 1.) 1.1.2 Class II Components of this c
5、lassification are fixed, ceramic dielectric capacitors of a type suited for bypass and decoupling application or for frequency discriminating circuits where Q and stability of capacitance characteristics are not of major importance. This classification is further defined as those capacitors having t
6、emperature characteristics A through S (see table 3). Class II ceramic dielectrics exhibit a predictable change with time and voltage. Compensation for the aging effect is made by referencing capacitance limits to a future time deemed to be most useful to the buyer; 1,000 hours is normally chosen, b
7、ut other arrangements may be negotiated between the buyer and seller. Voltage will also cause a temporary capacitance change, and the test sequence should be such that capacitance measurements are not affected by previous voltage tests. The aging rate of a dielectric is essentially constant over man
8、y decades of time, i.e., 10 h to 100 h, 100 h to 1,000 h, 1,000 h to 10,000 h, etc., when measured from the time of the last heat of depolarization in manufacture. Restoration of the original capacitance at time of manufacture will occur on heating to 150 oC for one hour, after which normal aging wi
9、ll again commence. Capacitors measured prior to 24 hours may exhibit temporarily high capacitance values that will age downward. 1.1.3 Class III Components herein standardized are fixed ceramic dielectric capacitors of a type specifically suited for use in electronic circuits for bypass, decoupling
10、or other applications in which dielectric losses, high insulation resistance and capacitance stability are not of major consideration. This classification is identical to that of class II, except that it is restricted to those capacitors having temperature characteristics T through V (table 3). 1.1.
11、4 Class IV This classification is restricted to those components utilizing reduced titanate or barrier layer type construction,. While basically fitting the descriptions of class II and class III, certain other electrical differences can be noted, as described in EIA-198-3-F of this specification. 1
12、.2 Mechanical classifications 1.2.1 Unleaded multilayer ceramic capacitors Unleaded ceramic chip capacitors are available in a variety of physical sizes and shapes lending themselves to a wide variety of specialized applications. Generally, the unit consists of an unencapsulated fired capacitor elem
13、ent with metallized terminations. A range of end metallizations is available to match the variety of possible bonding techniques. The absence of leads and any encapsulating material makes them extremely space efficient and well suited to hybrid circuit use in decoupling, bypassing, timing, tuning, e
14、tc. 1 Scope EIA-198-1-F Page 2 Generally, chip capacitors are available in dielectric classifications, I, II and III, suiting them for a wide range of hybrid applications where space is a prime consideration. The absence of lead inductance enables operation at considerably higher frequencies than co
15、mparable leaded units of the same capacitance value. Since these units are unencapsulated, they require an environment that minimizes the effects of humidity and contamination. Care must be taken to ensure that units are kept free or cleaned of ionizable residues deposited by handling or fluxing dur
16、ing manufacture. Care must also be exercised in the selection of substrate materials to minimize possible stresses due to differences in thermal expansion coefficients. Soldering methods, especially wave soldering, can cause thermal shock failures in unleaded surface-mounted capacitors. Susceptibili
17、ty to cracks caused by substrate thermal expansion, flexure, and thermal shock increases with body size. CC1210 bodies and larger, and CC0402 bodies and smaller, ceramic capacitor arrays, and any chips thicker than 1.7mm in height are generally not recommended for wave solder assembly, especially on
18、 the bottom of PC boards. 1.2.2 Leaded multilayer ceramic capacitors Leaded multilayer ceramics are available in both radial and axial lead configurations. Finished units consist of a multilayer chip attached to leads or lead frames and encapsulated with a protective environmental barrier. A large r
19、ange of capacitance values, case sizes and configurations are available which are suitable for manual or automatic insertion. Both axial and radial units are available in dielectric classifications I, II and III. These components are generally used in conventional printed circuit board (PCB) constru
20、ction at lower than ultrahigh frequencies (UHF). Typical applications include decoupling, bypassing, timing, filtering and tuning. The encapsulation of these units forms an environment barrier that allows unprotected operation in a variety of circuit environments. 1.2.3 Disk and tubular ceramic capa
21、citors Single layer disk, plates, and tubular capacitors are available in a variety of axial and/or radial styles. Units consist of a single layer of ceramic dielectric separating two electrodes. The entire assembly is encapsulated with a protective material. Typically, units are available lead tape
22、d and reeled for automatic insertion or bulk packed for manual assembly. Units available in dielectric classifications I, II, III and IV are typically used in conventional PCB assembly, in decoupling, bypassing, timing, filtering and tuning applications. Since their single layer construction (classe
23、s I, II, and III) can allow for higher voltage ratings than most common multilayer devices, these units have been preferred for applications where large working voltages are expected. 1.3 Type designation The type designation shall be in the form of the following examples: EIA designation_ Body code
24、 TC code Capacitance code_ Tolerance code_ Voltage code CC CC 025 1206 COG X7R 150 103 J K 500 101 1.3.1 EIA designator and body code The style designator consists of the two letter symbol “CC” (unless otherwise specified) followed by a two (2), three (3) or four (4) digit numeric code identifying s
25、hape and dimension of the capacitor body. “CC” is the EIA designation for ceramic capacitors. 1.3.2 Temperature characteristic (TC) code The TC code is identified by a letter-digit-letter symbol in accordance with tables 1 and 2 for class I dielectrics, and table 3 for classes II, III and IV dielect
26、rics. For class I dielectrics, the first letter identifies the nominal temperature coefficient, the digit identifies the multiplier and the final letter identifies the tolerance of the temperature coefficient. The temperature coefficient is expressed in parts per million per oC (ppm/oC) across the t
27、emperature range -55 oC to 85 oC except for multilayer capacitors where the maximum temperature is 125 oC. EIA-198-1-F Page 3 For classes II, III and IV, the first letter identifies the low-temperature requirement, the digit identifies the high temperature requirement, and the last letter identifies
28、 the maximum capacitance change in percent allowed across the specified range per table 3. 1.3.3 Calculation of temperature coefficient limits for class I The symmetrical tolerances apply to a 2-point measurement of temperature coefficient, one at +25 oC and the other at 85 oC (or 125 oC if specifie
29、d). To establish tolerances at -55 oC requires a calculation which allows for curvature: 1) The positive tolerance from +25 oC to -55 oC is the same as that used for +85 oC (or 125 oC if specified). 2) The negative tolerance from +25 oC to -55 oC (ppm/oC) = (-36) - (1.22 x specified positive toleran
30、ce) + (0.22 x nominal temperature coefficient) as shown in table 2. EXAMPLE 1Class I temperature coefficient calculation For P7H(+150 60 ppm/C at 85 C): Negative tolerance at -55 C=(-36)-1.22 x (+60)+0.22 x (+150)=-76.2 ppm/C Negative limit at 55 C = 150 76.2 = 73.8 ppm/C Positive limit at 55 C = 15
31、0 + 60.0 = 210 ppm/C EXAMPLE 2Class I temperature coefficient calculation For U2J(-750 120 ppm/C at 85 C): Negative tolerance at -55 C=(-36)-1.22 x (+120)+0.22 x (-750)=-347.4 ppm/C Negative limit at 55 C = (-750) 347.4 = -1097.4 ppm/C Positive limit at 55 C = (-750) + 120 = -630 ppm/C Table 1TC cod
32、es for class I ceramic dielectrics Alpha symbol Significant figure of temperature coefficient of capacitance ppm/oC Numerical symbol Multiplier applied to significant figure Alpha symbol Tolerance of temperature coefficient ppm/oC C B U A M P R S T U 0 0.3 0.8 0.9 1.0 1.5 2.2 3.3 4.7 7.5 0 1 2 3 4 5
33、 6 7 8 9 -1 -10 -100 -1000 -10000 +1 +10 +100 +1000 +10000 G H J K L M N 30 60 120 250 500 1000 2500 NOTE 1. These symmetrical tolerances apply to 2-point measurement of temperature coefficient, one at +25 oC and one at 85 oC unless otherwise specified. 2.Errors in measurements may limit ability to
34、determine TC tolerances on low capacitance values. EIA-198-1-F Page 4 Table 2 Permissible capacitance change from 25oC (ppm/oC) for class I ceramic dielectrics Characteristic Coefficients At -55 oC At +85 oC (or 125 oC if specified) Nominal TC PPM/oC TC code Most negative Most positive Most negative
35、 Most positive +150 P7K P7J P7H P7G -158 + 0 + 73 +110 +400 +270 +210 +180 -100 + 30 + 90 +120 +400 +270 +210 180 +100 M7K M7J M7H M7G -219 - 60 + 12 + 49 +350 +220 +160 +130 -150 - 20 + 40 + 70 +350 +220 +160 +130 + 33 S6K S6J S6H S6G -300 -142 - 68 - 32 +283 +153 +93 +63 - 217 - 87 - 27 + 3 +283 +
36、153 + 93 + 63 0 C0K C0J C0H C0G -341 -182 -109 - 72 +250 +120 + 60 + 30 -250 -120 - 60 - 30 +250 +120 + 60 + 30 - 33 S1K S1J S1H S1G - 381 - 222 - 149 - 112 +217 + 87 + 27 - 3 - 283 - 153 - 93 - 63 + 217 + 87 + 27 - 3 - 75 U1K U1J U1H U1G - 432 - 273 - 200 - 164 +175 + 45 - 15 - 45 - 325 - 195 - 135
37、 - 105 + 175 + 45 - 15 - 45 -150 P2K P2J P2H P2G - 524 - 365 - 292 - 255 +100 - 30 -90 -120 - 400 - 270 - 210 - 180 + 100 - 30 - 90 - 120 -220 R2K R2J R2H R2G - 609 - 450 - 377 - 341 + 30 -100 -160 -190 - 470 - 340 - 280 - 250 + 30 - 100 - 160 - 190 -330 S2L S2K S2J S2H -1048 - 743 - 585 - 511 +170
38、- 80 -210 -270 - 830 - 580 - 450 - 390 + 170 - 80 - 210 - 270 -470 T2K T2J T2H - 914 - 755 - 682 -220 -350 -410 - 720 - 590 - 530 - 220 - 350 - 410 -750 U2MU2K U2J U2H -2171 -1256 -1097 -1024 +250 -500 -630 -690 -1750 -1000 - 870 - 810 + 250 - 500 - 630 - 690 -1500 P3K -2171 -1250 -1750 -1250 -2200
39、R3L -3330 -1700 -2700 -1700 -3300 S3N S3L -7112 -4672 - 800 -2800 -5800 -3800 - 800 -2800 -4700 T3M -6990 -3700 -5700 -3700 EIA-198-1-F Page 5 Table 3TC codes and permissible capacitance change for class II, III and IV ceramic dielectrics Alpha symbol Low temperature C Numeric symbol High temperatur
40、e C Alpha symbol Max. cap. change over temp. range % Z Y X +10 -30 -55 2 4 5 6 7 8 9 +45 +65 +85 +105 +125 +150 +200 A B C D E F P R S T U V 1.0 1.5 2.2 3.3 4.7 7.5 10 15 22 +22 to -33 +22 to -56 +22 to -82 1.3.4 Capacitance code & tolerance code The capacitance and tolerance are identified by 3 dig
41、its and a letter symbol. The first and second digits identify the first and second significant figures of the capacitance, the third digit identifies the multiplier and the letter identifies the capacitance tolerance. See Table 5. Preferred values for nominal capacitance at typical tolerances are gi
42、ven in table 4 for 24, 12 and 6 steps per decade. Table 4Preferred nominal values for ceramic capacitor tolerance ranges 5% & lower 10% 20% & greater 5% & lower 10% 20% & greater 5% & lower 10% 20% & greater 10 10 10 22 22 22 47 47 47 11 24 51 12 12 27 27 56 56 13 30 62 15 15 15 33 33 33 68 68 68 16
43、 36 75 18 18 39 39 82 82 20 43 91 NOTE1. For values less than 10 pF, 0.5 pF, and ordinal values of 1.0 pF through 9.0 pF are also available. 2. For values =10uF for Y5V, E3 available, E1 preferred, and for X5R or X7R, E6 available, E3 preferred. EIA-198-1-F Page 6 Table 5Capacitance value and tolera
44、nce codes Capacitance code - pF (3 numeric characters) Tolerance - pF or % 1stsignificant 2ndsignificant Multiplier Capacitance range Alpha figure Figure Numeric code Equivalent multiplier =10 pF % code 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 1 10 100 1000 10000 100000 1000000 10
45、000000 0.01 0.1 0.05 0.10 0.25 0.50 A B C D 0.5 1 2 3 5 10 20 +100/-0 +80/-20 E F G H J K M P Z 1.3.5 Voltage code The voltage is identified by 3 digits. The first and second digits identify the first and second significant figures of the voltage and the third identifies the multiplier. See table 6
46、and the individual manufacturers specification sheets. Table 6Voltage and multiplier codes for ceramic capacitors 1st significant figure 2nd significant figure Numeric code Equivalent multiplier 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 9 1 10 100 1000 0.1 2.1 Leaded, encapsulated devices (mul
47、tilayer, plate, disk, tubular) Leaded capacitors shall be marked either by alphanumeric code (preferred) or by color code including capacitance, tolerance, temperature coefficient, voltage, manufacturer I.D. (name, trademark, EIA code number) where size permits. 2.1.1 Capacitance and tolerance Refer
48、 to table 8. Capacitance values less than 1000 pF will be expressed in picofarads. Capacitance values greater than or equal to 1000 pF will be expressed in capacitance codes. 2 Marking EIA-198-1-F Page 7 2.1.2 Temperature coefficients Refer to table 7. 2.1.2.1 Alphanumeric Alphanumeric TC codes will
49、 consist of three characters (for example X7R) or one code (for example C). 2.1.2.2 Color code The color code designation for TC type will be one (1) or two (2) dots or stripes depending on the temperature characteristic. The code designation for Hi-K type is always two (2) dots or stripes. 2.1.3 Voltage rating Refer to table 6. 2.2 Unleaded multilayer (chip) capacitors Unleaded (chip) capacitors, may be marked if required by the user. If this option is chosen, then the marking shall be as detailed
