Inductors

	Precautions for Use of Inductors
	Please click here for precautions of common matters for all products.
	Precautions for Use of Chip Inductors Inductors in General Soldering Mounting   Cleaning   Breakaway PC boards Environment for use   Storage of the products Other precautions Quality factor   Self resonant frequency   Allowable current

		Inductors in General

		The characteristics of L/Q values etc. of inductors have the frequency dependence. Confirm L/Q values etc. by the frequency for use on the actual machine.
		Pay attention to that the magnetic characteristics of the core and inductance may be changed by the stress of molded sealing and resin coating.
		Keep the inductors away from magnetic tweezers or magnets because magnetization may change the inductance. For prevention of disconnection, the wire wound portion of the chip inductor should not be touched by sharp things like tweezers etc.
		Inductance value might be decrease according to magnetic saturation when used exceeding the allowable current. There is a possibility of causing the disconnection and short-circuit by generation of heat of coil, and, in the worst case, is fear to smoking and the ignition.
		Please confirm before use because there is a risk of disconnection (open), when excessive current (inrush current) is flown by the occurrence of the transition phenomenon in the circuit of the electric charge and discharge. Also confirm taking the dispersion of the constants of other components on the actual circuit into the consideration.

		Soldering

		Soldering shall be performed within the temperature, the time, and the number of times, which is specified with technical specifications or precautions for each product. If the products are exposed in high temperature for long time, the change of color and characteristics and disconnection may be occurred.
		The body and the termination of the products shall not be touched by soldering iron.
		Avoid damage and physical shock to the products, when the products are nipped with hard tools like to pliers and tweezers.

		Mounting

		Avoid damage and physical shock to the product, because nipping with hard tools like to pliers and tweezers and imperfect adjustment of mounting machine may occur the fault such as change of characteristics, disconnection and crack.
		Some high frequency inductors have polarity in the characteristics of inductors. When mounting, those directions must be arranged.
		As non-magnetic shielded inductors, other components, chassis, substrate constructions, patterns, etc. may affect them to change L and Q. When high density mounting is applied, check the characteristic in advance on the actual conditions. Further, take care of positioning components as small spaces between inductors may cause magnetic interference. Do not place big magnetic materials like audio speakers etc. around the inductors.
		Do not give inductors heat radiation from other high temperature parts.

		Cleaning

		The ionic residue including solder must not remain after cleaning, causing the degradation of the resistance to moisture and corrosion.
		In case of adhesion of the ionic compounds such as sweat and salinity, sufficient cleaning after soldering should be performed in appropriate management of the cleaning agent. If the cleaning agent such as acid, alkaline, and organic solvent except for alcohols is used, consult us in advance for using.
		The ultrasonic cleaning may cause the destruction of the products because of resonance by vibration. The cleaning using high hydraulic pressure may also cause the deformation of the products. In these cases, confirm the cleaning condition in advance.
		Confirm to dry after cleaning sufficiently.

		Breakaway PC boards

		In case the products are arranged near groove line, the destruction of the product or termination may be occurred due to large stress when the board is split. Mount the products on the board in order to minimize the stress referred to the following figure.
		Make a proper layout to avoid the stress from the warp or deformation of the board not so as to add the stress as possible. Otherwise, the crack in solder and the destruction of the products may be occurred due to stress.

		Environment for use

		So far as special mentioned, the products do not suppose the use under a special environment. It should be confirmed to examine the performance and reliability in advance for using under the following special environments. 1. Use under direct sunrays, outside exposure and in dust. 2. Use in liquids such as water, oil, organic solvent and chemicals and in place where these liquids are splashed. 3. Use in places where the products are exposed to sea breeze or corrosive gases including SO2, H2S, Cl2, NH3, NO2 and etc. 4. Use in places with large static electricity and strong electromagnetic waves. 5. Use in places subject to dew condensation. 6. Use in case that the products or printed circuit boards are sealed and coated by resin or other coating materials. 7. Use in places where the products are exposed to the mist from lubricant oil.

		Storage of the products

		The products are stored in less dusty places where these are exposed to extremely high and low temperature, much of moisture, dew condensation, direct sunrays, sea breezes, corrosive gases such as SO2, H2S, Cl2, NH3, NO2 and etc. and mist from a lubricant oil. Use the desiccant if necessary.
		Consult us about the storage condition and period of the products.
		In bulk storage take care to avoid chipping core or disconnection caused by rubbing each other.

		Other precautions

		After placement, be sure to earth the equipment that measures the circuit with inductors assembled, etc. and to use a wrist band at the operation.

		Quality factor

		Quality factor is showing the quality of a coil and asks by the below formula.

		Self resonant frequency

		Frequency that resonants by distributed capacitance and inductance of coil.

		Allowable current

		Smaller allowable DC current either of the DC characteristics or the temperature rise.