Murata Manufacturing Co.,Ltd. is proud to announce that it has created a series of chip monolithic ceramic capacitors which feature metal pins and which are designed to be used in automotive electronic devices.
These capacitors will be showcased in Muratas booth at the Automotive Engineering Exposition scheduled to be held at PACIFICO Yokohama starting on May 18.
In the automotive market, the automakers, stimulated by the increasing interest focused in recent years on tackling global environmental problems and energy problems, have been pushing hard to develop hybrid electric vehicles (HEV) and electric vehicles (EV) and promote their practical use.
When chip monolithic ceramic capacitors (MLCC) - and especially large ones - are used in the automotive electronic devices installed on these HEVs and EVs, they are easily affected by the stress of the expansion and contraction of the substrates generated by sharp temperature changes, and under conditions where they will be exposed to thermal shock*1 occurring over long periods of time, measures to deal with solder cracks are an absolute necessity. Similarly, measures to deal with cracks in the capacitor elements that form as a result of vibration and mechanical impact must also be taken, and the capacitors are required to exhibit a higher level of reliability than when they are used in general - purpose products. So providing the capacitors with metal pins that have an elastic action reduces the impact to which the capacitor elements are subjected.
- The elastic action of the metal pins helps to reduce the amount of stress generated by thermal and mechanical impact and also makes the capacitors very reliable.
- By stacking a pair of capacitors one on top of the other, less space is required for mounting, and a high level of capacitance is achieved.
DC - DC converters in automotive ECUs*2, etc.
|*1 Thermal shock:||Sudden or abrupt changes in the ambient temperature|
|*2 ECU:||Electronic control unit - the computer that electronically controls the devices or systems in a motor vehicle|
* "****" denotes a 4 - digit number provided by Murata.
|Height (T) (mm)||Temperature characteristics||Static capacitance||Static capacitance tolerance||Murata
Solder cracks generated by thermal stress reduced to a minimum
|Test temperature:||-55 to +125 degrees Celsius|
|Time left standing:||5 minutes at each temperature level|
|Substrate used:||Glass epoxy substrate (FR - 4)|
|Chip size||Discrete chip
|Capacitor with metal pins
Fig. 1 Comparison of solder cracks generated by thermal stress (liquid bath test)
Fig. 2 Substrate warping test comparison
Fig. 3 Outline drawing (1 - level product)
Fig. 4 Outline drawing (2 - level product)
* The height (T) differs from one model number to another. For further details, refer to the [Parts number table].
Mass production scheduled to commence in July 2011
|Dates:||Wednesday, May 18 to Friday, May 20|
|Murata booth No. :||222|