Reference Specification
Metal Terminal Type Multilayer Ceramic Capacitors for General Purpose
( KRM31 Series [Rat. Vol.: DC25V to DC100V] )
Product specifications in this catalog are as of Apr.2022, and are subject to change or
obsolescence without notice.
Please consult the approval sheet before ordering.Please read rating and Cautions first.
Reference only
Caution
■Storage and Operation Conditions
1. The performance of chip monolithic ceramic capacitors may be affected by the storage conditions.
1-1. Store the capacitors in the following conditions:Room Temperature of +5°C to +40°C and a Relative Humidity
of 20% to 70%.
(1) Sunlight, dust, rapid temperature changes, corrosive gas atmosphere, or high temperature and humidity
conditions during storage may affect solderability and packaging performance. Therefore, please maintain
the storage temperature and humidity. Use the product within six months, as prolonged storage may cause
oxidation of the electrodes.
(2) Please confirm solderability before using after six months. Store the capacitors without opening the original bag.
Even if the storage period is short, do not exceed the specified atmospheric conditions.
1-2. Corrosive gas can react with the termination(external) electrodes or lead wires of capacitors, and result
in poor solderability. Do not store the capacitors in an atmosphere consisting of corrosive gas
(e.g., hydrogen sulfide, sulfur dioxide, chlorine, ammonia gas, etc.).
1-3. Due to moisture condensation caused by rapid humidity changes, or the photochemical change caused
by direct sunlight on the terminal electrodes and/or the resin/epoxy coatings, the solderability and electrical
performance may deteriorate. Do not store capacitors under direct sunlight or in high humidity conditions.
■Rating
1. Temperature Dependent Characteristics
1. The electrical characteristics of a capacitor can change with temperature.
1-1. For capacitors having larger temperature dependency, the capacitance may change with temperature changes.
The following actions are recommended in order to ensure suitable capacitance values.
(1) Select a suitable capacitance for the operating temperature range.
(2) The capacitance may change within the rated temperature. When you use a high dielectric constant type
capacitor in a circuit that needs a tight (narrow) capacitance tolerance (e.g., a time-constant circuit),
please carefully consider the temperature characteristics, and carefully confirm the various characteristics
in actual use conditions and the actual system.
2. Measurement of Capacitance
1. Measure capacitance with the voltage and frequency specified in the product specifications.
1-1. The output voltage of the measuring equipment may decrease occasionally when capacitance is high.
Please confirm whether a prescribed measured voltage is impressed to the capacitor.
1-2. The capacitance values of high dielectric constant type capacitors change depending on the AC voltage applied.
Please consider the AC voltage characteristics when selecting a capacitor to be used in an AC circuit.
3. Applied Voltage
1. Do not apply a voltage to the capacitor that exceeds the rated voltage as called out in the specifications.
1-1. Applied voltage between the terminals of a capacitor shall be less than or equal to the rated voltage.
(1) When AC voltage is superimposed on DC voltage, the zero-to-peak voltage shall not exceed the rated DC voltage.
When AC voltage or pulse voltage is applied, the peak-to-peak voltage shall not exceed the rated DC voltage.
(2) Abnormal voltages (surge voltage, static electricity, pulse voltage, etc.) shall not exceed the rated DC voltage.
Typical Voltage Applied to the DC Capacitor
DC Voltage
DC Voltage+AC
E
AC Voltage
E
E
Pulse Voltage
0
E
0
0
0
(E: Maximum possible applied voltage.)
1-2. Influence of over voltage
Over voltage that is applied to the capacitor may result in an electrical short circuit caused by the breakdown
of the internal dielectric layers. The time duration until breakdown depends on the applied voltage
and the ambient temperature.
2. Use a safety standard certified capacitor in a power supply input circuit (AC filter), as it is also necessary
to consider the withstand voltage and impulse withstand voltage defined for each device.
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Reference only
Caution
4. Type of Applied Voltage and Self-heating Temperature
1. Confirm the operating conditions to make sure that no large current is flowing into the capacitor due to the continuous
application of an AC voltage or pulse voltage. When a DC rated voltage product is used in an AC voltage circuit or a
pulse voltage circuit, the AC current or pulse current will flow into the capacitor; therefore check the self-heating condition.
Please confirm the surface temperature of the capacitor so that the temperature remains within the upper limits of the
operating temperature, including the rise in temperature due to self-heating. When the capacitor is used with a
high-frequency voltage or pulse voltage, heat may be generated by dielectric loss.
1-1. The load should be contained to the level such that when measuring at atmospheric temperature of 25℃, the product's
self-heating remains below 20℃ and the surface temperature of the capacitor in the actual circuit remains within the
maximum operating temperature.
1-2. The load should be contained so that the self-heating of the capacitor body remains below 20°C, when measuring at
an ambient temperature of 25°C. In addition, use a K thermocouple of φ0.1mm with less heat capacity when
measuring, and measure in a condition where there is no effect from the radiant heat of other components or air flow
caused by convection. Excessive generation of heat may cause deterioration of the characteristics and reliability of the
capacitor. (Absolutely do not perform measurements while the cooling fan is operating, as an accurate measurement
may not be performed.)
5. DC Voltage and AC Voltage Characteristics
1. The capacitance value of a high dielectric constant type capacitor changes depending on the DC voltage applied.
Please consider the DC voltage characteristics when a capacitor is selected for use in a DC circuit.
1-1. The capacitance of ceramic capacitors may change sharply depending on the applied voltage (see figure).
Please confirm the following in order to secure the capacitance.
(1) Determine whether the capacitance change caused by the applied voltage is within the allowed range.
(2) In the DC voltage characteristics, the rate of capacitance change becomes larger as voltage increases, even if the
applied voltage is below the rated voltage. When a high dielectric constant type capacitor is used in a circuit that
requires a tight (narrow) capacitance tolerance (e.g., a time constant circuit), please carefully consider the voltage
characteristics, and confirm the various characteristics in actual operating conditions in an actual system.
2. The capacitance values of high dielectric constant type capacitors changes depending on the AC voltage applied.
Please consider the AC voltage characteristics when selecting a capacitor to be used in an AC circuit.
6. Capacitance Aging
1. The high dielectric constant type capacitors have the characteristic in which the capacitance value decreases with the
passage of time. When you use high dielectric constant type capacitors in a circuit that needs a tight (narrow) capacitance
tolerance (e.g., a time-constant circuit), please carefully consider the characteristics of these capacitors, such as their
aging, voltage, and temperature characteristics. In addition, check capacitors using your actual appliances at the intended
environment and operating conditions.
7. Vibration and Shock
1. Please confirm the kind of vibration and/or shock, its condition, and any generation of resonance.
Please mount the capacitor so as not to generate resonance, and do not allow any impact on the terminals.
2. Mechanical shock due to being dropped may cause damage or a crack in the dielectric material of the capacitor.
Do not use a dropped capacitor because the quality and reliability may be deteriorated.
Crack
Floor
3. When printed circuit boards are piled up or handled, the corner of another printed circuit board should not be allowed
to hit the capacitor, in order to avoid a crack or other damage to the capacitor.
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Reference only
Caution
■Soldering and Mounting
1. Mounting Position
1. Confirm the best mounting position and direction that minimizes the stress imposed on the capacitor during flexing
or bending the printed circuit board.
1-1. Choose a mounting position that minimizes the stress imposed on the chip during flexing or bending of the board.
[Component Direction]
Locate chip horizontal to the direction in which stress acts.
[Chip Mounting Close to Board Separation Point]
It is effective to implement the following measures, to reduce stress in separating the board. It is best to implement all
of the following three measures; however, implement as many measures as possible to reduce stress.
C
Contents of Measures
Stress Level
(1) Turn the mounting direction of the component parallel
A>D
(1) to the board separation surface.
(2) Add slits in the board separation part.
A>B
D
A
(3) Keep the mounting position of the component away
Slit
A>C
(3) from the board separation surface.
[Mounting Capacitors Near Screw Holes]
When a capacitor is mounted near a screw hole, it may be affected by the board deflection that occurs during the
tightening of the screw. Mount the capacitor in a position as far away from the screw holes as possible.
Perforation
Screw Hole
B
Recommended
2.
1.
2.
3.
4.
5.
6.
7.
Information before Mounting
Do not re-use capacitors that were removed from the equipment.
Confirm capacitance characteristics under actual applied voltage.
Confirm the mechanical stress under actual process and equipment use.
Confirm the rated capacitance, rated voltage and other electrical characteristics before assembly.
Prior to use, confirm the solderability of capacitors that were in long-term storage.
Prior to measuring capacitance, carry out a heat treatment for capacitors that were in long-term storage.
The use of Sn-Zn based solder will deteriorate the reliability of the MLCC.
Please contact our sales representative or product engineers on the use of Sn-Zn based solder in advance.
8. We have also produced a DVD which shows a summary of our opinions, regarding the precautions for mounting.
Please contact our sales representative to request the DVD.
3. Maintenance of the Mounting (pick and place) Machine
1. Make sure that the following excessive forces are not applied to the capacitors.
1-1. In mounting the capacitors on the printed circuit board, any bending force against them shall be kept to a minimum
to prevent them from any bending damage or cracking. Please take into account the following precautions and
recommendations for use in your process.
(1) Adjust the lowest position of the pickup nozzle so as not to bend the printed circuit board.
(2) Adjust the nozzle pressure within a static load of 1N to 3N during mounting.
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Reference only
Caution
2. Dirt particles and dust accumulated between the suction nozzle and the cylinder inner wall prevent the nozzle from moving
moving smoothly. This imposes greater force upon the chip during mounting, causing cracked chips. Also, the locating
claw, when worn out, imposes uneven forces on the chip when positioning, causing cracked chips.
The suction nozzle and the locating claw must be maintained, checked, and replaced periodically.
4-1. Reflow Soldering
1. When sudden heat is applied to the components, the
mechanical strength of the components will decrease
because a sudden temperature change causes deformation
inside the components. In order to prevent mechanical damage
to the components, preheating is required for both the
components and the PCB. Preheating conditions are shown
in table 1. It is required to keep the temperature differential
between the solder and the components surface (ΔT) as small
as possible.
2. Solderability of tin plating termination chips might be
deteriorated when a low temperature soldering profile where
the peak solder temperature is below the melting point of tin
is used. Please confirm the solderability of tin plated
termination chips before use.
3. When components are immersed in solvent after mounting,
be sure to maintain the temperature difference (ΔT) between
the component and the solvent within the range shown in table 1.
[Standard Conditions for Reflow Soldering]
Temperature (℃)
Reflow
Soldering
Peak Temperature
220℃(200℃)
190℃(170℃)
170℃(150℃)
150℃(130℃)
Gradual
Cooling
ΔT
Preheating
Time
60 to 120 seconds
Temperature
Incase of Lead Free Solder
( ): In case of Pb-Sn Solder
Temperature (℃)
Vapor Reflow
Soldering
Peak Temperature
Table 1
Part Number
K□□21 / K□□31
K□□55
30 to 60 seconds
Temperature Differential
ΔT≦190°C
ΔT≦130°C
190℃(170℃)
170℃(150℃)
150℃(130℃)
Gradual
Cooling
ΔT
Preheating
Recommended Conditions
Pb-Sn Solder
Peak Temperature 230 to 250°C
Atmosphere
Air
Vapor Reflow
Lead Free
Solder
230 to 240°C
240 to 260°C
Saturated vapor
of inactive solvent
Air or N2
Time
60 to 120 seconds 20 seconds max.
[Allowable Reflow Soldering Temperature and Time]
Soldering Temperature
(℃)
Reflow
Pb-Sn Solder: Sn-37Pb
Lead Free Solder: Sn-3.0Ag-0.5Cu
280
270
260
250
240
230
220
0
90
120
Soldering Time (sec.)
In the case of repeated soldering, the accumulated
soldering time must be within the range shown above.
4. Optimum Solder Amount for Reflow Soldering
4-1. If solder paste is excessive, solder between a chip and a
metal terminal melts. This causes the chip to move and
come off.
4-2. If solder paste is too little, it causes a lack of adhesive
strength on the metal terminal and the capacitor comes off.
4-3. Please make sure that solder is smoothly applied higher
than 0.3mm and lower than the level of the bottom of the
chip.
Inverting the PCB
Make sure not to impose any abnormal mechanical shocks to the PCB.
4-2. Flow Soldering
1. Do not apply flow soldering.
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30
60
0.3mm min.
In section
Reference only
Caution
4-3. Correction of Soldered Portion
1. For the shape of the soldering iron tip, refer to the figure
on the right.
2. Regarding the type of solder, use a wire diameter of
φ0.5mm or less (rosin core wire solder).
3. Apply the tip of the soldering iron against the lower end
of the metal terminal.
(1) In order to prevent cracking caused by sudden heating
of the ceramic device, do not touch the ceramic base
directly.
(2) In order to prevent deviations and dislocating of the
chip, do not touch the junction of the chip and the metal
terminal, and the metal portion on the outside directly.
4. The amount of solder for corrections by soldering iron,
should be lower than the height of the lower side of the chip.
Solder Amount
In section
5. Washing
Excessive ultrasonic oscillation during cleaning can cause the PCBs to resonate, resulting in cracked chips or broken
solder joints. Take note not to vibrate PCBs.
6. Electrical Test on Printed Circuit Board
1. Confirm position of the backup pin or specific jig, when inspecting the electrical performance of a capacitor after
mounting on the printed circuit board.
1-1. Avoid bending the printed circuit board by the pressure of a test-probe, etc. The thrusting force of the test probe can
flex the PCB, resulting in cracked chips or open solder joints. Provide backup pins on the back side of the PCB
to prevent warping or flexing. Install backup pins as close to the capacitor as possible.
1-2. Avoid vibration of the board by shock when a test-probe contacts a printed circuit board.
[Not Recommended]
[Recommended]
Peeling
Backup Pin
Test-probe
Test-probe
7. Printed Circuit Board Cropping
1. After mounting a capacitor on a printed circuit board, do not apply any stress to the capacitor that causes bending
or twisting the board.
1-1. In cropping the board, the stress as shown at right may cause the capacitor to crack. Cracked capacitors may cause
deterioration of the insulation resistance, and result in a short. Avoid this type of stress to a capacitor.
[Bending]
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[Twisting]
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Reference only
Caution
2. Check the cropping method for the printed circuit board in advance.
2-1. Printed circuit board cropping shall be carried out by using a jig or an apparatus (Disk separator, router type separator,
etc.) to prevent the mechanical stress that can occur to the board.
Board Separation Method
Hand Separation
Nipper Separation
(1) Board Separation Jig
Level of stress on board
High
Recommended
×
Notes
Hand and nipper separation
apply a high level of stress.
Use another method.
Board Separation Apparatus
(2) Disk Separator
(3) Router Type Separator
Medium
Medium
Low
△*
△*
○
· Board handling
· Board bending direction
· Layout of capacitors
· Board handling
· Layout of slits
· Design of V groove
· Arrangement of blades
· Controlling blade life
Board handling
* When a board separation jig or disk separator is used, if the following precautions are not observed, a large board deflection stress will occur and the capacitors
may crack. Use router type separator if at all possible.
(1) Example of a suitable jig
[In the case of Single-side Mounting]
An outline of the board separation jig is shown as follows. Recommended example: Stress on the component
mounting position can be minimized by holding the portion close to the jig, and bend in the direction towards
the side where the capacitors are mounted. Not recommended example: The risk of cracks occurring in the
capacitors increases due to large stress being applied to the component mounting position, if the portion away
from the jig is held and bent in the direction opposite the side where the capacitors are mounted.
[Outline of Jig]
Recommended
Not Recommended
[In the case of Double-sided Mounting]
Since components are mounted on both sides of the board, the risk of cracks occurring can not be avoided with the
above method. Therefore, implement the following measures to prevent stress from being applied to the components.
(Measures)
① Consider introducing a router type separator. If it is difficult to introduce a router type separator, implement
the following measures. (Refer to item 1. Mounting Position)
② Mount the components at a right angle to the board separation surface.
③ When mounting components near the board separation point, add slits in the separation position
near the component.
④ Keep the mounting position of the components away from the board separation point.
(2) Example of a Disk Separator
An outline of a disk separator is shown as follows. As shown in the Principle of Operation, the top blade and bottom
blade are aligned with the V-grooves on the printed circuit board to separate the board. In the following case, board
deflection stress will be applied and cause cracks in the capacitors.
① When the adjustment of the top and bottom blades are misaligned, such as deviating in the top-bottom, left-right
or front-rear directions
② The angle of the V groove is too low, depth of the V groove is too shallow, or the V groove is misaligned
top-bottom IF V groove is too deep, it is possible to brake when you handle and carry it. Carefully design depth of
the V groove with consideration about strength of material of the printed circuit board.
[Outline of Machine]
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[Principle of Operation]
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[Cross-section Diagram]
Reference only
Caution
Recommended
Top Blade
Top Blade
Bottom Blade
Example of
Recommended
V-groove Design
Not Recommended
Left-right Misalignment
Top-bottom Misalignment
Bottom Blade
Left-right Misalignment
Front-rear Misalignment
Top Blade
Bottom Blade
Not Recommended
Low-Angle
Depth too Shallow
Top Blade
Bottom Blade
Depth too Deep
(3) Example of Router Type Separator
The router type separator performs cutting by a router rotating at a high speed. Since the board does not bend in the
cutting process, stress on the board can be suppressed during board separation. When attaching or removing
boards to/from the router type separator, carefully handle the boards to prevent bending.
[Outline Drawing]
Router
8. Assembly
1. Handling
If a board mounted with capacitors is held with one hand, the board may bend. Firmly hold the edges of the board with
both hands when handling. If a board mounted with capacitors is dropped, cracks may occur in the capacitors.
Do not use dropped boards, as there is a possibility that the quality of the capacitors may be impaired.
2. Attachment of Other Components
2-1. Mounting of Other Components
Pay attention to the following items, when mounting other
components on the back side of the board after capacitors
have been mounted on the opposite side. When the bottom
dead point of the suction nozzle is set too low, board deflection
stress may be applied to the capacitors on the back side
Suction Nozzle
(bottom side), and cracks may occur in the capacitors.
・ After the board is straightened, set the bottom dead point
of the nozzle on the upper surface of the board.
・ Periodically check and adjust the bottom dead point.
2-2. Inserting Components with Leads into Boards
When inserting components (transformers, IC, etc.) into boards,
bending the board may cause cracks in the capacitors or
cracks in the solder. Pay attention to the following.
・ Increase the size of the holes to insert the leads, to reduce
the stress on the board during insertion.
・ Fix the board with backup pins or a dedicated jig before
Component with Leads
insertion.
・ Support below the board so that the board does not bend.
When using multiple backup pins on the board, periodically
confirm that there is no difference in the height of each
backup pin.
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Reference only
Caution
2-3. Attaching/Removing Sockets
When the board itself is a connector, the board may bend when
a socket is attached or removed. Plan the work so that the board
does not bend when a socket is attached or removed.
2-4. Tightening Screws
The board may be bent, when tightening screws, etc. during the
attachment of the board to a shield or chassis.
Pay attention to the following items before performing the work.
・ Plan the work to prevent the board from bending.
・ Use a torque screwdriver, to prevent over-tightening of the
screws.
・ The board may bend after mounting by reflow soldering, etc.
Please note, as stress may be applied to the chips by forcibly
flattening the board when tightening the screws.
Socket
Screwdriver
■Other
1. Under Operation of Equipment
1-1. Do not touch a capacitor directly with bare hands during operation in order to avoid the danger of an electric shock.
1-2. Do not allow the terminals of a capacitor to come in contact with any conductive objects (short-circuit). Do not
expose a capacitor to a conductive liquid, including any acid or alkali solutions.
1-3. Confirm the environment in which the equipment will operate is under the specified conditions. Do not use
the equipment under the following environments.
(1) Being spattered with water or oil.
(2) Being exposed to direct sunlight.
(3) Being exposed to ozone, ultraviolet rays, or radiation.
(4) Being exposed to toxic gas (e.g., hydrogen sulfide, sulfur dioxide, chlorine, ammonia gas, etc.)
(5) Any vibrations or mechanical shocks exceeding the specified limits.
(6) Moisture condensing environments.
1-4. Use damp proof countermeasures if using under any conditions that can cause condensation.
2. Other
2-1. In an Emergency
(1) If the equipment should generate smoke, fire, or smell, immediately turn off or unplug the equipment. If the
equipment is not turned off or unplugged, the hazards may be worsened by supplying continuous power.
(2) In this type of situation, do not allow face and hands to come in contact with the capacitor or burns may be
caused by the capacitor's high temperature.
2-2. Disposal of Waste
When capacitors are disposed of, they must be burned or buried by an industrial waste vendor with the appropriate
licenses.
2-3. Circuit Design
(1) Addition of Fail Safe Function
Capacitors that are cracked by dropping or bending of the board may cause deterioration of the insulation
resistance, and result in a short. If the circuit being used may cause an electrical shock, smoke or fire when
a capacitor is shorted, be sure to install fail-safe functions, such as a fuse, to prevent secondary accidents.
(2) Capacitors used to prevent electromagnetic interference in the primary AC side circuit, or as a
connection/insulation, must be a safety standard certified product, or satisfy the contents stipulated
in the Electrical Appliance and Material Safety Law. Install a fuse for each line in case of a short.
(3) The KR3, KRM, KC3, KCM series are not safety standard certified products.
2-4. Remarks
Failure to follow the cautions may result, worst case, in a short circuit and smoking when the product is used.
The above notices are for standard applications and conditions. Contact us when the products are used
in special mounting conditions. Select optimum conditions for operation as they determine the reliability of
the product after assembly. The data herein are given in typical values, not guaranteed ratings.
3. Limitation of applications
Please contact us before using our products for the applications listed below which require especially high reliability
for the prevention of defects which might directly cause damage to the third party’s life, body or property.
(1) Aircraft equipment
(2) Aerospace equipment
(3) Undersea equipment
(4) Power plant control equipment
(5) Medical equipment
(6) Transportation equipment (vehicles, trains, ships, etc.)
(7) Traffic signal equipment
(8) Disaster prevention/crime prevention equipment
(9) Data-processing equipment exerting influence on public
(10) Application of similar complexity and/or reliability requirements to the applications listed in the above.
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Reference only
Notice
■Rating
1. Operating Temperature
1. The operating temperature limit depends on the capacitor.
1-1. Do not apply temperatures exceeding the upper operating temperature. It is necessary to select a capacitor with
a suitable rated temperature that will cover the operating temperature range. It is also necessary to consider
the temperature distribution in equipment and the seasonal temperature variable factor.
1-2. Consider the self-heating factor of the capacitor. The surface temperature of the capacitor shall be the upper
operating temperature or less when including the self-heating factors.
2. Atmosphere Surroundings (gaseous and liquid)
1. Restriction on the operating environment of capacitors.
1-1. Capacitors, when used in the above, unsuitable, operating environments may deteriorate due to the corrosion
of the terminations and the penetration of moisture into the capacitor.
1-2. The same phenomenon as the above may occur when the electrodes or terminals of the capacitor are subject
to moisture condensation.
1-3. The deterioration of characteristics and insulation resistance due to the oxidization or corrosion of terminal
electrodes may result in breakdown when the capacitor is exposed to corrosive or volatile gases or solvents
for long periods of time.
3. Piezo-electric Phenomenon
1. When using high dielectric constant type capacitors in AC or pulse circuits, the capacitor itself vibrates at specific
frequencies and noise may be generated. Moreover, when the mechanical vibration or shock is added to the capacitor,
noise may occur.
■Soldering and Mounting
1. PCB Design
1. Notice for Pattern Forms
1-1. Unlike leaded components, chip components are susceptible to flexing stresses since they are mounted directly
on the substrate. They are also more sensitive to mechanical and thermal stresses than leaded components.
Excess solder fillet height can multiply these tresses and cause chip cracking. When designing substrates,
take land patterns and dimensions into consideration to eliminate the possibility of excess solder fillet height.
1-2. There is a possibility of chip cracking caused by PCB expansion/contraction with heat, because stress on a chip is
different depending on PCB material and structure. When the thermal expansion coefficient greatly differs between
the board used for mounting and the chip, it will cause cracking of the chip due to the thermal expansion and
contraction. When small size capacitors of 1005 size or less are mounted on a single-layered glass epoxy board,
it will also cause cracking of the chip for the same reason.
Pattern Forms
Prohibited
Chassis
Solder(ground)
Correct
Solder Resist
Placing Close to Chassis
Electrode Pattern
Placing
of Chip Components
and Leaded Components
Placing
of Leaded Components
after Chip Component
Lead Wire
Solder Resist
Soldering Iron
Lead Wire
Solder Resist
Solder Resist
Lateral Mounting
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Notice
2. Land Dimensions
2-1. Chip capacitors can be cracked due to the stress of PCB
bending, etc. if the land area is larger than needed and
has an excess amount of solder. Please refer to the land
dimensions in the following table for reflow soldering.
Please confirm the suitable land dimension by evaluating
of the actual SET / PCB.
Part Number
K□□21
K□□31
K□□55
Dimensions
Chip (L×W)
a
b
c
2.0×1.25
3.2×1.6
5.7×5.0
1.0 to 1.2
2.2 to 2.4
2.6
0.6 to 0.7
0.8 to 0.9
2.7
0.8 to 1.1
1.0 to 1.4
5.6
3. Board Design
When designing the board, keep in mind that the amount of strain which occurs will increase depending on the size
and material of the board.
Relationship with amount of strain to the board thickness, length, width, etc.]
ε=
3PL
2Ewh2
Relationship between load and strain
P
Y
h
L
w
ε:Strain on center of board (μst)
L:Distance between supporting points (mm)
w :Board width (mm)
h :Board thickness (mm)
E :Elastic modulus of board (N/m2=Pa)
Y :Deflection (mm)
P :Load (N)
When the load is constant, the following relationship can be established.
· As the distance between the supporting points (L) increases,the amount of strain also increases.
→Reduce the distance between the supporting points.
· As the elastic modulus (E) decreases, the amount of strain increases.
→Increase the elastic modulus.
· As the board width (w) decreases, the amount of strain increases.
→Increase the width of the board.
· As the board thickness (h) decreases, the amount of strain increases.
→Increase the thickness of the board.
Since the board thickness is squared, the effect on the amount of strain becomes even greater.
4. Washing
1. Please evaluate the capacitor using actual cleaning equipment and conditions to confirm the quality, and select the
solvent for cleaning.
2. Unsuitable cleaning solvent may leave residual flux or other foreign substances, causing deterioration of electrical
characteristics and the reliability of the capacitors.
3. Select the proper cleaning conditions.
3-1. Improper cleaning conditions (excessive or insufficient) may result in deterioration of the performance of the capacitors.
5. Coating
1. A crack may be cause in the capacitor due to the stress of the thermal contraction of the resin during curing process. The
stress is affected by the amount of resin and curing contraction. Select a resin with low curing contraction. The difference
in the thermal expansion coefficient between a coating resin or a molding resin and the capacitor may cause the
destruction and deterioration of the capacitor such as a crack or peeling, and lead to the deterioration of insulation
resistance or dielectric breakdown. Select a resin for which the thermal expansion coefficient is as close to that of the
capacitor as possible. A silicone resin can be used as an under-coating to buffer against the stress.
2. Select a resin that is less hygroscopic. Using hygroscopic resins under high humidity conditions may cause
the deterioration of the insulation resistance of a capacitor. An epoxy resin can be used as a less hygroscopic resin.
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Reference only
Notice
■Other
1. Transportation
1. The performance of a capacitor may be affected by the conditions during transportation.
1-1. The capacitors shall be protected against excessive temperature, humidity, and mechanical force during
transportation.
(1) Climatic condition
・ low air temperature : -40℃
・ change of temperature air/air : -25℃/+25℃
・ low air pressure : 30kPa
・ change of air pressure : 6kPa/min.
(2) Mechanical condition
Transportation shall be done in such a way that the boxes are not deformed and forced are not directly passed
on to the inner packaging.
1-2. Do not apply excessive vibration, shock, or pressure to the capacitor.
(1) When excessive mechanical shock or pressure is applied to a capacitor, chipping or cracking may occur
in the ceramic body of the capacitor.
(2) When the sharp edge of an air driver, a soldering iron, tweezers, a chassis, etc. impacts strongly on the surface
of the capacitor, the capacitor may crack and short-circuit.
1-3. Do not use a capacitor to which excessive shock was applied by dropping, etc. A capacitor dropped accidentally
during processing may be damaged.
2. Characteristics Evaluation in the Actual System
1. Evaluate the capacitor in the actual system, to confirm that there is no problem with the performance and specification
values in a finished product before using.
2. Since a voltage dependency and temperature dependency exists in the capacitance of high dielectric type ceramic
capacitors, the capacitance may change depending on the operating conditions in the actual system. Therefore,
be sure to evaluate the various characteristics, such as the leakage current and noise absorptivity, which will affect
the capacitance value of the capacitor.
3. In addition, voltages exceeding the predetermined surge may be applied to the capacitor by the inductance in the actual
system. Evaluate the surge resistance in the actual system as required.
Note
1. Please make sure that your product has been evaluated in view of your specifications with our product being mounted
to your product.
2. You are requested not to use our product deviating from this specification.
EGKRC01
11 / 20
Reference only
1. Application
This specification is applied to Metal Terminal Type Multilayer Ceramic Capacitors KRM series
used for General Electronics equipment.
Do not use these products in any automotive power train or safety equipment including battery
chargers for electric vehicles and plug-in hybrids.
2. Rating
2-1. Operating temperature range
2-2. Part name configuration
31
K
ex.) KRM
Series
Chip
Height
dimension dimension
(LW)
Chip dimension(LW)
Code
31
Height dimension
Code
F
K
Char. X5R : -55 to +85°C
Char. X6S : -55 to +105°C
Char. X7R : -55 to +125°C
C8
YA
106
K
H01
K
Temperature Rated Capacitance Capacitance Individual Packing
characteristic voltage
tolerance specification style
Nominal Chip dimension (mm)
L
W
3.2
1.6
Dimension (mm)
1.9
2.7
Please refer to [Part number list] on the dimensions of metal terminal product.
Temperature characteristic
Code
Temperature characteristic
R6
X5R
R7
X7R
C8
X6S
Please confirm detailed specification on [Specification and test methods].
Rated voltage
Code
1E
YA
1H
2A
Rated voltage
DC25V
DC35V
DC50V
DC100V
Capacitance
The first two digits denote significant figures ; the last digit denotes the multiplier of 10 in pF.
Ex.) In case 106.
10x106 = 10000000pF(=10F)
Capacitance tolerance
Please refer to [Part number list].
ETKRM3101A
12 / 20
Reference only
Individual specification
Murata’s control code
Please refer to Part number list .
Packing style
Code
K
Style
330mm reel Plastic taping
ETKRM3101A
13 / 20
Reference only
3. Part number list
Unit : mm
DC
Rated Cap.
T.C.
Volt. (F)
(V)
Cap.
tol.
(%)
Dimension(mm)
Customer Part Number
Murata Part Number
L
W
T
e
Pack
Chip
qty.
type
(pcs)
X5R
25
10
±10
KRM31FR61E106KH01K
3.5
±0.3
1.7
±0.2
1.9
0.8
±0.1 ±0.2
1
5000
X6S
25
10
±10
KRM31KC81E106KH01K
3.5
±0.3
1.7
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
X6S
35
10
±10
KRM31KC8YA106KH01K
3.5
±0.3
1.7
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
X7R
50
2.2
±10
KRM31KR71H225KH01K
3.6
±0.3
1.7
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
X7R
50
4.7
±10
KRM31KR71H475KH01K
3.5
±0.3
1.7
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
X7R
100
1.0
±10
KRM31KR72A105KH01K
3.5
±0.3
1.7
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
X7R
100
2.2
±10
KRM31KR72A225KH01K
3.7
±0.3
1.85
±0.2
2.7
0.8
±0.2 ±0.2
1
4000
ETKRM3101A
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Reference only
4. Specifications and test methods
No.
Item
1
Operating temperature
range
2
3
4
Appearance
Dimensions
Dielectric strength
Specifications
Char. X5R : -55 to +85°C
Char. X6S : -55 to +105°C
Char. X7R : -55 to +125°C
No defects or abnormalities
Within the specified dimension.
No defects or abnormalities.
Test method
Visual inspection.
Using calipers and micrometers.
No failure should be observed when voltage
in the table is applied between the trminations
for 1 to 5 s, provided the charge/discharge
current is less than 50mA.
Rated Voltage
DC25V, DC35V,
DC50V
DC100V
5
Insulation
resistance(I.R.)
6
Capacitance
7
Dissipation
Factor (D.F.)
8
Capacitance
Temperature
Characteristics
Rated Voltage
DC25V, DC35V
DC50V , DC100V
50MF or more
500MF or more
Within the specified tolerance.
Rated Voltage
DC25V, DC35V
DC50V
DC100V
D.F.
0.15 max.
0.025 max.
0.05 max.
Temp.(C)
1
252
10 Solderability of
termination
The insulation resistance should be
measured with rated voltage and within
60±5 s of charging.
Nominal
capacitance
Measuring
frequency
C>10μF
12024Hz
C≦10μF
10.2kHz
2
The metal surface is soldered well.
Measuring
volgate
AC0.50.1V
(r.m.s.)
AC1.00.2V
(r.m.s.)
The capacitance measurement should be
made at each step specified in the table.
•Pretreatment
Perform the heat treatment at 150+0/-10°C
for 60±5 min and then let sit for 24±2 h at
room condition*.
3
Min. Operating Temp.
Vibration
Appearance No defects or abnormalities.
resistance Capacitance Within the specified tolerance.
D.F.
Pass the item No.7.
250% of the rated voltage
200% of the rated voltage
The capacicance/D.F.should be measured at
reference temperature at the meaning
frequency and voltage shown in the table.
Char. X5R : within ±15%
(Temp.Range:-55 to +85°C)
Char. X6S : within ±22%
(Temp.Range:-55 to +105°C)
Char. X7R : within ±15%
(Temp.Range:-55 to +125°C)
Step
9
I.R.
Test Voltage
3
252
4
5
Max. Operating Temp.
2
252
Solder the capacitor to the Test Jig A (glass
epoxy board) shown in “Complement of test
method”.
The capacitor should be subjected to a
simple harmonic motion having a total
amplitude of 1.5mm, the frequency being
varied uniformly between the approximate
limits of 10 and 55Hz .
The frequency range, from 10 to 55Hz and
return to 10Hz, should be traversed in
approximately 1 min.
This motion should be applied for a period of
2 h in each of 3 mutually perpendicular
directions (total of 6 h).
Reflow Soldering : Peak 260+0/-5C
The area of soldering 230C min., 20 to 40 s
Let sit for 24±2 h at room condition*, then
measure.
•Pretreatment
Perform the heat treatment at 150+0/-10°C
for 60±5 min and then let sit for 24±2 h at
room condition*.
260+0/-5°C
300°C
20 to 40 s
230°C
min.
200°C
180°C
150°C
100°C
60 to 120 s
* "room condition" Temperature:15 to 35°C, Relative humidity:45 to 75%, Atmosphere pressure:86 to 106kPa
ESKRM3101
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Reference only
No.
Item
11 Resistance Appearance
to soldering Capacitance
heat
change
D.F.
I.R.
Dielectric
strength
12 Adhesive strength
of termination
Specifications
No marking defects.
Within ±10%
Test method
Reflow Soldering
・See Item 10 Solderability of termination
Pass the item No.7.
Pass the item No.5.
Pass the item No.4.
In a soldering iron case
Temp. of solder : 350±10C
Solder time : 4+1/-0 s
Let sit for 24±2 h at room condition*, then
measure.
No removal of the terminations
or other defects should occur.
Please refer to 「
Caution 4-3. Correction
of Soldered Portion」
Solder the capacitor to the Test Jig A (glass
epoxy board) shown in “Complement of Test
method”.
Then apply 10N force in the direction of the
arrow.
10N ,10±1 s
Glass Epoxy Board
13 Deflection
No marking defects.
14 Strength of metal terminal Termination not to be broken or
loosened.
15 Temperature Appearance No marking defects.
cycle
Capacitance Within ±7.5%
change
D.F.
Pass the item No.7.
I.R.
Pass the item No.5.
Dielectric
Pass the item No.4.
strength
16 Humidity
(Steady
state)
Appearance No marking defects.
Capacitance Within ±15%
change
D.F.
Rated Voltage
DC25V, DC35V
DC50V , DC100V
I.R.
Rated Voltage
DC25V, DC35V
DC50V , DC100V
Solder the capacitor to the Test Jig B(glass
epoxy board) shown in “Complement of test
method”.
Then apply the force in the direction shown in
“Test Method of Deflection” of “Complement
of test method”.
・Flexure : 5mm
・Hold time : 5 s
A static load
Pressure
of 10N using
Pressure
jig
a pressure
jig should be
applied to the
center in the
direction of the
arrow and held
for 10 s.
Fix the capacitor to the supporting Test Jig A
(glass epoxy board) shown in “Complement
of test method”.
Perform the 100 cycles according to the
4 heat treatments listed in the following table.
Step
1
2
3
4
D.F.
0.2 max.
0.05 max.
I.R.
Temp. (°C)
Min. Operating Temp.±3
Room Temp.
Max. Operating Temp.±2
Room Temp.
Time (min)
30±3
2 to 3
30±3
2 to 3
Let sit for 24±2 h at room condition*, then
measure.
•Pretreatment
Perform the heat treatment at 150+0/-10°C
for 60±5 min and then let sit for 24±2 h at
room condition*.
Sit the capacitor at 40±2°C and relative
humidity 90 to 95% for 500+24/-0 h.
Remove and let sit for 24±2 h at room
condition*, then measure.
•Pretreatment
Perform the heat treatment at 150+0/-10°C
for 60±5 min and then let sit for 24±2 h at
room condition*.
12.5MF or more
50MF or more
Dielectric
Pass the item No.4.
strength
* “room condition” Temperature:15 to 35°C, Relative humidity:45 to 75%, Atmosphere pressure:86 to 106kPa
ESKRM3101
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Reference only
No.
17 Life
Item
Specifications
Appearance No marking defects.
Capacitance Within ±15%
change
D.F.
Rated Voltage
DC25V, DC35V
DC50V , DC100V
I.R.
Rated Voltage
DC25V, DC35V
DC50V , DC100V
D.F.
0.2 max.
0.05 max.
I.R.
Test method
Apply 150% of the rated voltage for
1000+48/-0 h at maximum operating
temperature±3°C.
Remove and let sit for 24±2 h at room
condition*, then measure.
The charge/discharge current is less than
50mA.
•Pretreatment
Apply test voltage for 60±5 min at test
temperature.
25MF or more
50MF or more
Dielectric
Pass the item No.4.
strength
* “room condition” Temperature:15 to 35°C, Relative humidity:45 to 75%, Atmosphere pressure:86 to 106kPa
ESKRM3101
17 / 20
Reference only
Complement of Test Method
Test Jig
The test jig should be Jig A or Jig B as described in “Specifications and Test methods”.
The specimen should be soldered by the conditions as described below.
Soldering Method : Reflow soldering
Thickness of Metal-mask : 150µm
Solder : Sn-3.0Ag-0.5Cu
c
(1) Test Jig A
a
2.2
a
b
Dimension (mm)
Solder resist
b
5.0
c
1.65
Baked electrode or copper foil
Material : Glass Epoxy Board
Thickness : 1.6mm
Thickness of copper foil : 0.035mm
(2) Test Jig B
a
d
c
Dimension (mm)
40
a
2.2
(4.5)
b
100
1.6
Copper foil
Solder resist
Material : Glass Epoxy Board
Thickness of copper foil : 0.035mm
ESKRM3101
18 / 20
(unit : mm)
b
5.0
c
1.65
d
1.0
Reference only
5. Packing (Taping is standard packing method)
(1) Appearance of taping
(a) Plastic Tape
Cover Tape (Thickness: Around 60m) is put on capacitor on Base Tape (Blister carrier Tape).
(b) The sprocket holes are to the right as the Tape is pulled toward the user.
(2) Packed capacitors
Capacitor
1.5+0.1/-0
4.00.1
4.00.1
2.00.05
1.750.1
(3) Dimensions of Tape
0.30.1
5.50.05
B
12.00.3
A
C max.
(Unit : mm)
Nominal value
Part Number
K□□31K
K□□31F
A
2.2
2.2
B
4.1
4.1
C
4.1
2.8
100+1/-0
(4) Dimensions of Reel
2.00.5
φ210.8
17.51.5
3302.0
φ130.2
13.51.0
(Unit : mm)
(5) Part of the leader and part of the empty tape should be attached to the end of the tape as follows.
Vacant section : 160 min.
Capacitors mounting unit
Vacant section : 190 min.
210 min.
Direction of feed
(Unit : mm)
EKTK3101
19 / 20
Reference only
(6) The top tape or cover tape and base tape are not attached at the end of the tape for a minimum of
5 pitches.
(7) Missing capacitors number within 0.1% of the number per reel or 1pc, whichever is greater, and not
continuous
(8) The top tape or cover tape and bottom tape should not protrude beyond the edges of the tape and
should not cover sprocket holes.
(9) Cumulative tolerance of sprocket holes, 10 pitches : ±0.3mm.
(10) Peeling off force : 0.1 to 0.6N in the direction shown on the follows.
165 to 180°
Top Tape or Cover Tape
Base Tape
EKTK3101
20 / 20