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MIL-PRF-55681 / Chips

Part Number Example CDR31 thru CDR35

MIL-PRF-55681 / Chips
Part Number Example CDR31 thru CDR35
MILITARY DESIGNATION PER MIL-PRF-55681
Part Number Example
(example)
CDR31
MIL Style Voltage-temperature Limits
Capacitance Rated Voltage Capacitance Tolerance Termination Finish Failure Rate
CROSS REFERENCE: AVX / MIL-PRF-55681 / CDR31 THRU CDR35
Per MIL-PRF-55681 (Metric Sizes) CDR31 CDR32 CDR33 CDR34 CDR35 AVX Style 0805 1206 1210 1812 1825 Length (L) (mm) 2.00 3.20 3.20 4.50 4.50 Width (W) (mm) 1.25 1.60 2.50 3.20 6.40 Thickness (T) Max. (mm) 1.3 1.3 1.5 1.5 1.5 D Min. (mm) .50 - - - - Termination Band (t) Max. (mm) .70 .70 .70 .70 .70 Min. (mm) .30 .30 .30 .30 .30
MIL-PRF-55681 / Chips
Military Part Number Identification CDR31
CDR31 to MIL-PRF-55681 / 7
Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits
AVX Style 0805 / CDR31 (BP)
CDR31BP1R0B-CDR31BP1R1B-CDR31BP1R2B-CDR31BP1R3B-CDR31BP1R5B-CDR31BP1R6B-CDR31BP1R8B-CDR31BP2R0B-CDR31BP2R2B-CDR31BP2R4B-CDR31BP2R7B-CDR31BP3R0B-CDR31BP3R3B-CDR31BP3R6B-CDR31BP3R9B-CDR31BP4R3B-CDR31BP4R7B-CDR31BP5R1B-CDR31BP5R6B-CDR31BP6R2B-CDR31BP6R8B-CDR31BP7R5B-CDR31BP8R2B-CDR31BP9R1B-CDR31BP100B-CDR31BP110B-CDR31BP120B-CDR31BP130B-CDR31BP150B-CDR31BP160B-CDR31BP180B-CDR31BP200B-CDR31BP220B-CDR31BP240B-CDR31BP270B-CDR31BP300B-CDR31BP330B-CDR31BP360B-CDR31BP390B-CDR31BP430B-CDR31BP470B-CDR31BP510B-CDR31BP560B-CDR31BP620B-CDR31BP680B-CDR31BP750B-CDR31BP820B-CDR31BP910B-1.0 1.1 1.2 1.3 1.5 1.6 1.8 2.0 2.2 2.4 2.7 3.0 3.3 3.6 3.9 4.3 4.7 5.1 5.6 6.2 6.8 7.5 8.2 9.1 10 11 12 13 15 16 18 20 22 24 27 30 33 36 39 43 47 51 56 62 68 75 82 91 B, C B, C B, C B, C B, C B, C B, C B, C B, C B, C B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
CDR31BP101B-CDR31BP111B-CDR31BP121B-CDR31BP131B-CDR31BP151B-CDR31BP161B-CDR31BP181B-CDR31BP201B-CDR31BP221B-CDR31BP241B-CDR31BP271B-CDR31BP301B-CDR31BP331B-CDR31BP361B-CDR31BP391B-CDR31BP431B-CDR31BP471B-CDR31BP511A-CDR31BP561A-CDR31BP621A-CDR31BP681A-100 110 120 130 150 160 180 200 220 240 270 300 330 360 390 430 470 510 560 620 680 F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 50 50 50 50
AVX Style 0805 / CDR31 (BX)
CDR31BX471B-CDR31BX561B-CDR31BX681B-CDR31BX821B-CDR31BX102B-CDR31BX122B-CDR31BX152B-CDR31BX182B-CDR31BX222B-CDR31BX272B-CDR31BX332B-CDR31BX392B-CDR31BX472B-CDR31BX562A-CDR31BX682A-CDR31BX822A-CDR31BX103A-CDR31BX123A-CDR31BX153A-CDR31BX183A-470 560 680 820 1, 000 1, 200 1, 500 1, 800 2, 200 2, 700 3, 300 3, 900 4, 700 5, 600 6, 800 8, 200 10, 000 12, 000 15, 000 18, 000 K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX BX 100 100 100 100 100 100 100 100 100 100 100 100 100 50 50 50 50 50 50 50
Add appropriate failure rate Add appropriate termination finish Capacitance Tolerance 1 / The complete part number will include additional symbols to indicate capacitance tolerance, termination and failure rate level.
Add appropriate failure rate Add appropriate termination finish Capacitance Tolerance
MIL-PRF-55681 / Chips
Military Part Number Identification CDR32
CDR32 to MIL-PRF-55681 / 8
Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits
AVX Style 1206 / CDR32 (BP)
CDR32BP1R0B-CDR32BP1R1B-CDR32BP1R2B-CDR32BP1R3B-CDR32BP1R5B-CDR32BP1R6B-CDR32BP1R8B-CDR32BP2R0B-CDR32BP2R2B-CDR32BP2R4B-CDR32BP2R7B-CDR32BP3R0B-CDR32BP3R3B-CDR32BP3R6B-CDR32BP3R9B-CDR32BP4R3B-CDR32BP4R7B-CDR32BP5R1B-CDR32BP5R6B-CDR32BP6R2B-CDR32BP6R8B-CDR32BP7R5B-CDR32BP8R2B-CDR32BP9R1B-CDR32BP100B-CDR32BP110B-CDR32BP120B-CDR32BP130B-CDR32BP150B-CDR32BP160B-CDR32BP180B-CDR32BP200B-CDR32BP220B-CDR32BP240B-CDR32BP270B-CDR32BP300B-CDR32BP330B-CDR32BP360B-CDR32BP390B-CDR32BP430B-CDR32BP470B-CDR32BP510B-CDR32BP560B-CDR32BP620B-CDR32BP680B-CDR32BP750B-CDR32BP820B-CDR32BP910B-1.0 1.1 1.2 1.3 1.5 1.6 1.8 2.0 2.2 2.4 2.7 3.0 3.3 3.6 3.9 4.3 4.7 5.1 5.6 6.2 6.8 7.5 8.2 9.1 10 11 12 13 15 16 18 20 22 24 27 30 33 36 39 43 47 51 56 62 68 75 82 91 B, C B, C B, C B, C B, C B, C B, C B, C B, C B, C B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
CDR32BP101B-CDR32BP111B-CDR32BP121B-CDR32BP131B-CDR32BP151B-CDR32BP161B-CDR32BP181B-CDR32BP201B-CDR32BP221B-CDR32BP241B-CDR32BP271B-CDR32BP301B-CDR32BP331B-CDR32BP361B-CDR32BP391B-CDR32BP431B-CDR32BP471B-CDR32BP511B-CDR32BP561B-CDR32BP621B-CDR32BP681B-CDR32BP751B-CDR32BP821B-CDR32BP911B-CDR32BP102B-CDR32BP112A-CDR32BP122A-CDR32BP132A-CDR32BP152A-CDR32BP162A-CDR32BP182A-CDR32BP202A-CDR32BP222A-100 110 120 130 150 160 180 200 220 240 270 300 330 360 390 430 470 510 560 620 680 750 820 910 1, 000 1, 100 1, 200 1, 300 1, 500 1, 600 1, 800 2, 000 2, 200 F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 50 50 50 50 50 50 50 50
AVX Style 1206 / CDR32 (BX)
CDR32BX472B-CDR32BX562B-CDR32BX682B-CDR32BX822B-CDR32BX103B-CDR32BX123B-CDR32BX153B-CDR32BX183A-CDR32BX223A-CDR32BX273A-CDR32BX333A-CDR32BX393A-4, 700 5, 600 6, 800 8, 200 10, 000 12, 000 15, 000 18, 000 22, 000 27, 000 33, 000 39, 000 K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M BX BX BX BX BX BX BX BX BX BX BX BX 100 100 100 100 100 100 100 50 50 50 50 50
Add appropriate failure rate Add appropriate termination finish Capacitance Tolerance
Add appropriate failure rate Add appropriate termination finish Capacitance Tolerance 1 / The complete part number will include additional symbols to indicate capacitance tolerance, termination and failure rate level.
MIL-PRF-55681 / Chips
Military Part Number Identification CDR33 / 34 / 35
CDR33 / 34 / 35 to MIL-PRF-55681 / 9 / 10 / 11
Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits Military Type Designation 1 / Capacitance in pF Rated temperature WVDC Capacitance and voltagetolerance temperature limits
AVX Style 1210 / CDR33 (BP)
CDR33BP102B-CDR33BP112B-CDR33BP122B-CDR33BP132B-CDR33BP152B-CDR33BP162B-CDR33BP182B-CDR33BP202B-CDR33BP222B-CDR33BP242A-CDR33BP272A-CDR33BP302A-CDR33BP332A-1, 000 1, 100 1, 200 1, 300 1, 500 1, 600 1, 800 2, 000 2, 200 2, 400 2, 700 3, 000 3, 300 F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 50 50 50 50
AVX Style 1812 / CDR34 (BX)
CDR34BX273B-CDR34BX333B-CDR34BX393B-CDR34BX473B-CDR34BX563B-CDR34BX104A-CDR34BX124A-CDR34BX154A-CDR34BX184A-27, 000 33, 000 39, 000 47, 000 56, 000 100, 000 120, 000 150, 000 180, 000 K, M K, M K, M K, M K, M K, M K, M K, M K, M BX BX BX BX BX BX BX BX BX 100 100 100 100 100 50 50 50 50
AVX Style 1825 / CDR35 (BP)
CDR35BP472B-CDR35BP512B-CDR35BP562B-CDR35BP622B-CDR35BP682B-CDR35BP752B-CDR35BP822B-CDR35BP912B-CDR35BP103B-CDR35BP113A-CDR35BP123A-CDR35BP133A-CDR35BP153A-CDR35BP163A-CDR35BP183A-CDR35BP203A-CDR35BP223A-4, 700 5, 100 5, 600 6, 200 6, 800 7, 500 8, 200 9, 100 10, 000 11, 000 12, 000 13, 000 15, 000 16, 000 18, 000 20, 000 22, 000 F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 50 50 50 50 50 50 50 50
AVX Style 1210 / CDR33 (BX)
CDR33BX153B-CDR33BX183B-CDR33BX223B-CDR33BX273B-CDR33BX393A-CDR33BX473A-CDR33BX563A-CDR33BX683A-CDR33BX823A-CDR33BX104A-15, 000 18, 000 22, 000 27, 000 39, 000 47, 000 56, 000 68, 000 82, 000 100, 000 K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M BX BX BX BX BX BX BX BX BX BX 100 100 100 100 50 50 50 50 50 50
AVX Style 1812 / CDR34 (BP)
CDR34BP222B-CDR34BP242B-CDR34BP272B-CDR34BP302B-CDR34BP332B-CDR34BP362B-CDR34BP392B-CDR34BP432B-CDR34BP472B-CDR34BP512A-CDR34BP562A-CDR34BP622A-CDR34BP682A-CDR34BP752A-CDR34BP822A-CDR34BP912A-CDR34BP103A-2, 200 2, 400 2, 700 3, 000 3, 300 3, 600 3, 900 4, 300 4, 700 5, 100 5, 600 6, 200 6, 800 7, 500 8, 200 9, 100 10, 000 F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K F, J, K BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP 100 100 100 100 100 100 100 100 100 50 50 50 50 50 50 50 50
AVX Style 1825 / CDR35 (BX)
CDR35BX563B-CDR35BX683B-CDR35BX823B-CDR35BX104B-CDR35BX124B-CDR35BX154B-CDR35BX184A-CDR35BX224A-CDR35BX274A-CDR35BX334A-CDR35BX394A-CDR35BX474A-56, 000 68, 000 82, 000 100, 000 120, 000 150, 000 180, 000 220, 000 270, 000 330, 000 390, 000 470, 000 K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M K, M BX BX BX BX BX BX BX BX BX BX BX BX 100 100 100 100 100 100 50 50 50 50 50 50
Add appropriate failure rate Add appropriate failure rate Add appropriate termination finish Add appropriate termination finish Capacitance Tolerance Capacitance Tolerance 1 / The complete part number will include additional symbols to indicate capacitance tolerance, termination and failure rate level.
Packaging of Chip Components
Automatic Insertion Packaging
TAPE & REEL QUANTITIES
All tape and reel specifications are in compliance with RS481.
8mm Paper or Embossed Carrier Embossed Only Paper Only Qty. per Reel / 7" Reel Qty. per Reel / 13" Reel 0201, 0306, 0402, 0603 2, 000, 3, 000 or 4, 000, 10, 000, 15, 000
Contact factory for exact quantity
REEL DIMENSIONS
Tape Size(1) 8mm
A Max.
B Min.
D Min.
N Min.
W2 Max. 14.4 (0.567)
W3 7.90 Min. (0.311) 10.9 Max. (0.429) 11.9 Min. (0.469) 15.4 Max. (0.607)
330 (12.992) 12mm
Metric dimensions will govern. English measurements rounded and for reference only. (1) For tape sizes 16mm and 24mm (used with chip size 3640) consult EIA RS-481 latest revision.
Embossed Carrier Configuration
8 & 12mm Tape Only
Chip Orientation
CENTER LINES OF CAVITY
P1 MAX. CAVITY SIZE - SEE NOTE 1
D1 FOR COMPONENTS 2.00 mm x 1.20 mm AND LARGER (0.079 x 0.047)
B1 IS FOR TAPE READER REFERENCE ONLY INCLUDING DRAFT CONCENTRIC AROUND B0
User Direction of Feed
8 & 12mm Embossed Tape Metric Dimensions Will Govern
CONSTANT DIMENSIONS
Tape Size 8mm and 12mm D0 1.50 (0.059
S1 Min. 0.60 (0.024)
T Max. 0.60 (0.024)
T1 0.10 (0.004) Max.
VARIABLE DIMENSIONS
2.50 Max. (0.098) 6.50 Max. (0.256) 2.50 Max. (0.098) 6.50 Max. (0.256)
See Note 1
12mm 8mm 1 / 2 Pitch 12mm Double Pitch
See Note 1
Top View, Sketch "F" Component Lateral Movements 0.50mm (0.020) Maximum
0.50mm (0.020) Maximum
Paper Carrier Configuration
8 & 12mm Tape Only
8 & 12mm Paper Tape Metric Dimensions Will Govern
CONSTANT DIMENSIONS
Tape Size 8mm and 12mm D0 1.50 (0.059
T1 0.10 (0.004) Max.
G. Min. 0.75 (0.030) Min.
R Min. 25.0 (0.984) See Note 2 Min.
VARIABLE DIMENSIONS
A0 B0 See Note 1
12mm 8mm 1 / 2 Pitch 12mm Double Pitch
1.10mm (0.043) Max. for Paper Base Tape and 1.60mm (0.063) Max. for Non-Paper Base Compositions
Top View, Sketch "C" Component Lateral 0.50mm (0.020) Maximum
0.50mm (0.020) Maximum
Bar Code Labeling Standard
AVX bar code labeling is available and follows latest version of EIA-556
Bulk Case Packaging
BENEFITS
· Easier handling · Smaller packaging volume
(1 / 20 of T / R packaging)
BULK FEEDER
· Easier inventory control · Flexibility · Recyclable
Cassette Gate
CASE DIMENSIONS
Shutter Slider 12mm 36mm Expanded Drawing 110mm Attachment Base
Shooter
Mounter Head Chips
CASE QUANTITIES
Basic Capacitor Formulas
D C / decade of time
METRIC PREFIXES
Pico Nano Micro Milli Deci Deca Kilo Mega Giga Tera X 10-12 X 10-9 X 10-6 X 10-3 X 10-1 X 10+1 X 10+3 X 10+6 X 10+9 X 10+12
SYMBOLS
X&Y Lo
General Description
Ceramic Layer
Electrode End Terminations
Terminated Edge
Margin
Electrodes
Multilayer Ceramic Capacitor Figure 1
Formulations - Multilayer ceramic capacitors are available in both Class 1 and Class 2 formulations. Temperature compensating formulation are Class 1 and temperature stable and general application formulations are classified as Class 2. Class 1 - Class 1 capacitors or temperature compensating capacitors are usually made from mixtures of titanates where barium titanate is normally not a major part of the mix. They have predictable temperature coefficients and in general, do not have an aging characteristic. Thus they are the most stable capacitor available. The most popular Class 1 multilayer ceramic capacitors are C0G (NP0) temperature compensating capacitors (negative-positive 0 ppm / °C).
General Description
Effects of Voltage - Variations in voltage have little effect on Class 1 dielectric but does affect the capacitance and dissipation factor of Class 2 dielectrics. The application of DC voltage reduces both the capacitance and dissipation factor while the application of an AC voltage within a reasonable range tends to increase both capacitance and dissipation factor readings. If a high enough AC voltage is applied, eventually it will reduce capacitance just as a DC voltage will. Figure 2 shows the effects of AC voltage.
Cap. Change vs. A.C. Volts X7R
Capacitance Change Percent 50 40 30 20 10 0 12.5 25 37.5 Volts AC at 1.0 KHz 50
Figure 2
Capacitor specifications specify the AC voltage at which to measure (normally 0.5 or 1 VAC) and application of the wrong voltage can cause spurious readings. Figure 3 gives the voltage coefficient of dissipation factor for various AC voltages at 1 kilohertz. Applications of different frequencies will affect the percentage changes versus voltages.
D.F. vs. A.C. Measurement Volts X7R
10.0 Dissipation Factor Percent Curve 1 - 100 VDC Rated Capacitor 8.0 Curve 2 - 50 VDC Rated Capacitor Curve 3 - 25 VDC Rated Capacitor 6.0 4.0 2.0 0 .5 1.0 1.5 2.0 2.5 AC Measurement Volts at 1.0 KHz Curve 1 Curve 3 Curve 2
Temperature characteristic is specified by combining range and change symbols, for example BR or AW. Specification slash sheets indicate the characteristic applicable to a given style of capacitor.
In specifying capacitance change with temperature for Class 2 materials, EIA expresses the capacitance change over an operating temperature range by a 3 symbol code. The first symbol represents the cold temperature end of the temperature range, the second represents the upper limit of the operating temperature range and the third symbol represents the capacitance change allowed over the operating temperature range. Table 1 provides a detailed explanation of the EIA system.
Figure 3
Typical effect of the application of DC voltage is shown in Figure 4. The voltage coefficient is more pronounced for higher K dielectrics. These figures are shown for room temperature conditions. The combination characteristic known as voltage temperature limits which shows the effects of rated voltage over the operating temperature range is shown in Figure 5 for the military BX characteristic.
General Description
Typical Cap. Change vs. D.C. Volts X7R
tends to de-age capacitors and is why re-reading of capacitance after 12 or 24 hours is allowed in military specifications after dielectric strength tests have been performed.
Typical Curve of Aging Rate X7R
Figure 4
Typical Cap. Change vs. Temperature X7R
Capacitance Change Percent +20 +10 0VDC 0 -10 -20 -30 -55 -35 -15 +5 +25 +45 +65 +85 +105 +125
-6.0 -7.5 1 10 100 1000 10, 000 100, 000 Hours
Characteristic C0G (NP0) X7R, X5R Y5V
Figure 6
Temperature Degrees Centigrade
Figure 5
Effects of Time - Class 2 ceramic capacitors change capacitance and dissipation factor with time as well as temperature, voltage and frequency. This change with time is known as aging. Aging is caused by a gradual re-alignment of the crystalline structure of the ceramic and produces an exponential loss in capacitance and decrease in dissipation factor versus time. A typical curve of aging rate for semistable ceramics is shown in Figure 6. If a Class 2 ceramic capacitor that has been sitting on the shelf for a period of time, is heated above its curie point, (125°C for 4 hours or 150°C for 1 / 2 hour will suffice) the part will de-age and return to its initial capacitance and dissipation factor readings. Because the capacitance changes rapidly, immediately after de-aging, the basic capacitance measurements are normally referred to a time period sometime after the de-aging process. Various manufacturers use different time bases but the most popular one is one day or twenty-four hours after "last heat." Change in the aging curve can be caused by the application of voltage and other stresses. The possible changes in capacitance due to de-aging by heating the unit explain why capacitance changes are allowed after test, such as temperature cycling, moisture resistance, etc., in MIL specs. The application of high voltages such as dielectric withstanding voltages also
General Description
Effects of Mechanical Stress - High "K" dielectric ceramic capacitors exhibit some low level piezoelectric reactions under mechanical stress. As a general statement, the piezoelectric output is higher, the higher the dielectric constant of the ceramic. It is desirable to investigate this effect before using high "K" dielectrics as coupling capacitors in extremely low level applications. Reliability - Historically ceramic capacitors have been one of the most reliable types of capacitors in use today. The approximate formula for the reliability of a ceramic capacitor is:
Energy Stored - The energy which can be stored in a capacitor is given by the formula:
where
Historically for ceramic capacitors exponent X has been considered as 3. The exponent Y for temperature effects typically tends to run about 8. A capacitor is a component which is capable of storing electrical energy. It consists of two conductive plates (electrodes) separated by insulating material which is called the dielectric. A typical formula for determining capacitance is:
General Description
I (Ideal) I (Actual) Loss Angle
Phase Angle
E.S.R.
Surface Mounting Guide
MLC Chip Capacitors
REFLOW SOLDERING
Dimensions in millimeters (inches)
Case Size 0402 0603 0805 1206 1210 1808 1812 1825 2220 2225
Component Pad Design
WAVE SOLDERING
Case Size 0603 0805 1206
Dimensions in millimeters (inches)
Component Spacing
For wave soldering components, must be spaced sufficiently far apart to avoid bridging or shadowing (inability of solder to penetrate properly into small spaces). This is less important for reflow soldering but sufficient space must be allowed to enable rework should it be required.
Preheat & Soldering
The rate of preheat should not exceed 4°C / second to prevent thermal shock. A better maximum figure is about 2°C / second. For capacitors size 1206 and below, with a maximum thickness of 1.25mm, it is generally permissible to allow a temperature differential from preheat to soldering of 150°C. In all other cases this differential should not exceed 100°C. For further specific application or process advice, please consult AVX.
Cleaning
1.5mm (0.06) 1mm (0.04)
1mm (0.04)
Care should be taken to ensure that the capacitors are thoroughly cleaned of flux residues especially the space beneath the capacitor. Such residues may otherwise become conductive and effectively offer a low resistance bypass to the capacitor. Ultrasonic cleaning is permissible, the recommended conditions being 8 Watts / litre at 20-45 kHz, with a process cycle of 2 minutes vapor rinse, 2 minutes immersion in the ultrasonic solvent bath and finally 2 minutes vapor rinse.
Surface Mounting Guide
MLC Chip Capacitors
APPLICATION NOTES
Storage
300 Preheat 250 200 150 100 50 Natural Cooling
Solderability
Solder Temp.
230°C to 250°C
Leaching
3 sec. max
Recommended Soldering Profiles
Reflow
300 250 200 150 100 50 220°C to 250°C Preheat Natural Cooling
(Preheat chips before soldering) T / maximum 150°C
Lead-Free Wave Soldering
The recommended peak temperature for lead-free wave soldering is 250°C-260°C for 3-5 seconds. The other parameters of the profile remains the same as above. The following should be noted by customers changing from lead based systems to the new lead free pastes. a) The visual standards used for evaluation of solder joints will need to be modified as lead free joints are not as bright as with tin-lead pastes and the fillet may not be as large. b) Resin color may darken slightly due to the increase in temperature required for the new pastes. c) Lead-free solder pastes do not allow the same self alignment as lead containing systems. Standard mounting pads are acceptable, but machine set up may need to be modified.
Solder Temp.
10 sec. max
(Minimize soldering time)
General
Surface mounting chip multilayer ceramic capacitors are designed for soldering to printed circuit boards or other substrates. The construction of the components is such that they will withstand the time / temperature profiles used in both wave and reflow soldering methods.
Lead-Free Reflow Profile
300 250 200 150 100 50 0 0 Temperature °C
Handling
Chip multilayer ceramic capacitors should be handled with care to avoid damage or contamination from perspiration and skin oils. The use of tweezers or vacuum pick ups is strongly recommended for individual components. Bulk handling should ensure that abrasion and mechanical shock are minimized. Taped and reeled components provides the ideal medium for direct presentation to the placement machine. Any mechanical shock should be minimized during handling chip multilayer ceramic capacitors.
250 Time (s)
Preheat
It is important to avoid the possibility of thermal shock during soldering and carefully controlled preheat is therefore required. The rate of preheat should not exceed 4°C / second
Surface Mounting Guide
MLC Chip Capacitors
and a target figure 2°C / second is recommended. Although an 80°C to 120°C temperature differential is preferred, recent developments allow a temperature differential between the component surface and the soldering temperature of 150°C (Maximum) for capacitors of 1210 size and below with a maximum thickness of 1.25mm. The user is cautioned that the risk of thermal shock increases as chip size or temperature differential increases.
POST SOLDER HANDLING
Soldering
Mildly activated rosin fluxes are preferred. The minimum amount of solder to give a good joint should be used. Excessive solder can lead to damage from the stresses caused by the difference in coefficients of expansion between solder, chip and substrate. AVX terminations are suitable for all wave and reflow soldering systems. If hand soldering cannot be avoided, the preferred technique is the utilization of hot air soldering tools.
Cooling
Natural cooling in air is preferred, as this minimizes stresses within the soldered joint. When forced air cooling is used, cooling rate should not exceed 4°C / second. Quenching is not recommended but if used, maximum temperature differentials should be observed according to the preheat conditions above.
Cleaning
Flux residues may be hygroscopic or acidic and must be removed. AVX MLC capacitors are acceptable for use with all of the solvents described in the specifications MIL-STD202 and EIA-RS-198. Alcohol based solvents are acceptable and properly controlled water cleaning systems are also acceptable. Many other solvents have been proven successful, and most solvents that are acceptable to other components on circuit assemblies are equally acceptable for use with ceramic capacitors.
Type A: Angled crack between bottom of device to top of solder joint.
Type B: Fracture from top of device to bottom of device.
Mechanical cracks are often hidden underneath the termination and are difficult to see externally. However, if one end termination falls off during the removal process from PCB, this is one indication that the cause of failure was excessive mechanical stress due to board warping.
Surface Mounting Guide
MLC Chip Capacitors
COMMON CAUSES OF MECHANICAL CRACKING
REWORKING OF MLCs
Solder Tip
Preferred Method - No Direct Part Contact
Poor Method - Direct Contact with Part
PCB BOARD DESIGN
To avoid many of the handling problems, AVX recommends that MLCs be located at least .2" away from nearest edge of board. However when this is not possible, AVX recommends that the panel be routed along the cut line, adjacent to where the MLC is located.
No Stress Relief for MLCs
Routed Cut Line Relieves Stress on MLC