Achieving High Ripple Current Resistance and High Effective Capacitance! Murata Launches Massproduction of GeneralPurpose KR3 Series and AutomotiveUse KC3 Series Metal Terminal Monolithic Ceramic Capacitors
Overview
Murata Manufacturing Co. Ltd. has launched mass production of metal terminal monolithic ceramic capacitors that achieve high ripplecurrent resistance and high effective capacitance.
The KR3 series for generalpurpose applications and KC3 series for automotive applications are now available. The KR3 series capacitors comply with JIS standards and are optimal for general consumer and industrial electronic devices that are subject to thermal stress and/or vibration/mechanical impact. On the other hand, the KC3 series capacitors comply with the automotive electronic components standard known as AECQ200 and are optimal for automotive equipment such as engines, engine control units (ECU) , drive system control, and safety devices.
Background and Details
With rising concern toward global environmental issues and energy issues in recent years, the automobile market is endorsing practical applications of Hybrid Electric Vehicles (HEV) and Electric Vehicles (EV) . Since thermal resistance is a key requirement of electronic components for HEV and EV applications, there is a demand for capacitors that are resistant to high temperatures. In response to this demand, Murata has developed monolithic ceramic capacitors that have high ripplecurrent resistance (low selfheat generation) using newly developed ceramic materials.
There is also an increasing demand for small and longlife ceramic capacitors with high capacitance as a replacement for electrolytic capacitors and film capacitors used as smoothing capacitors. To meet this demand, Murata uses new materials to assure a high effective capacitance by suppressing the characteristic that lowers electrostatic capacity when a DC bias is applied (during operation) .
Furthermore, there is a possibility that cracks may occur in a capacitor element and solder joints of mounted components due to thermal stress or vibration/mechanical impact. Therefore, crack prevention measures must be provided for automobiles, general electronic devices, and industrial electronic devices that are used under such conditions. Murata has reduced the effects of impact to chip elements and solder joints of mounted components by attaching metal terminals with an elastic action to the capacitors.
Features
High ripplecurrent resistance
Since it has low loss and a high allowable current capacity, the heat generation of the capacitor (selfheat generation) can be reduced at the time of passing current.
Example: (See the upper right graph below.) The new material product has approximately 1.6 times higher allowable current capacity at a frequency (f) of 250kHz. In the case of products with a capacitance of 1μF when the heating temperature is 20°C at a frequency (f) of 250kHz, the allowable current capacity of capacitors made of conventional materials is 2.9Arms whereas that of capacitors made of the new material is 4.7Arms.
High effective capacitance
It is possible to reduce the drop in capacitance while a DC bias is applied, as well as assure high effective capacitance value.
Example: Approximately twice higher capacitance is assured when DC250V is applied.
Applications
Generalpurpose applications (KR3 series)
 Smoothing and EMI filter for LED lighting
 Used for the Power Factor Correction (PFC) circuit in the switching power supplies and AC adaptor
 DCDC converter for general electronic devices
Automotive applications (KC3 series)
 Used for drive system control in equipment such as engines and ECUs
 Used for other drive system controls and safety devices
Part List
KR3 series capacitors for generalpurpose applications
Rated voltage (DC) 
Length (L) x Width (W) (mm) 
Thickness (T) (mm) 
Temperature characteristics 
Capacitance  Capacitance tolerance 
Murata part number 

250V  6.1 x 5.3  2.8±0.2  X7T  0.47µF  ±10%  KR355LD72E474 KH01K 
6.1 x 5.3  3.7±0.2  X7T  1µF  ±10%  KR355QD72E105 KH01K 

6.1 x 5.3  6.4±0.3  X7T  2.2µF  ±20%  KR355WD72E225 MH01K 

450V  6.1 x 5.3  2.8±0.2  X7T  0.22µF  ±10%  KR355LD72W224 KH01K 
6.1 x 5.3  2.8±0.2  X7T  0.47µF  ±10%  KR355LD72W474 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.56µF  ±10%  KR355QD72W564 KH01K 

6.1 x 5.3  4.8±0.2  X7T  1µF  ±20%  KR355TD72W105 MH01K 

6.1 x 5.3  6.4±0.3  X7T  1.2µF  ±20%  KR355WD72W125 MH01K 

630V  6.1 x 5.3  2.8±0.2  X7T  0.1µF  ±10%  KR355LD72J104 KH01K 
6.1 x 5.3  4.8±0.2  X7T  0.15µF  ±20%  KR355LD72J154 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.22µF  ±10%  KR355QD72J224 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.27µF  ±10%  KR355QD72J274 KH01K 

6.1 x 5.3  6.4±0.3  X7T  0.47µF  ±20%  KR355WD72J474 MH01K 

6.1 x 5.3  6.4±0.3  X7T  0.56µF  ±20%  KR355WD72J564 MH01K 
KC3 series capacitors for automotive applications
Rated voltage (DC) 
Length (L) x Width (W) (mm) 
Thickness (T) (mm) 
Temperature characteristics 
Capacitance  Capacitance tolerance 
Murata part number 

250V  6.1 x 5.3  2.8±0.2  X7T  0.47µF  ±10%  KC355LD72E474 KH01K 
6.1 x 5.3  3.7±0.2  X7T  1µF  ±10%  KC355QD72E105 KH01K 

6.1 x 5.3  6.4±0.3  X7T  2.2µF  ±20%  KC355WD72E225 MH01K 

450V  6.1 x 5.3  2.8±0.2  X7T  0.22µF  ±10%  KC355LD72W224 KH01K 
6.1 x 5.3  2.8±0.2  X7T  0.47µF  ±10%  KC355LD72W474 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.56µF  ±10%  KC355QD72W564 KH01K 

6.1 x 5.3  4.8±0.2  X7T  1µF  ±20%  KC355TD72W105 MH01K 

6.1 x 5.3  6.4±0.3  X7T  1.2µF  ±20%  KC355WD72W125 MH01K 

630V  6.1 x 5.3  2.8±0.2  X7T  0.1µF  ±10%  KC355LD72J104 KH01K 
6.1 x 5.3  4.8±0.2  X7T  0.15µF  ±20%  KC355LD72J154 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.22µF  ±10%  KC355QD72J224 KH01K 

6.1 x 5.3  3.7±0.2  X7T  0.27µF  ±10%  KC355QD72J274 KH01K 

6.1 x 5.3  6.4±0.3  X7T  0.47µF  ±20%  KC355WD72J474 MH01K 

6.1 x 5.3  6.4±0.3  X7T  0.56µF  ±20%  KC355WD72J564 MH01K 
External Size
*Note: Thickness (T) varies depending on part number. For further details, see the "Parts List."
Production
Mass production is being carried out at Izumo Murata Manufacturing Co., Ltd. from September 2012.