Fixed Inductors

Image	Part Number	Description / PDF	Quantity	Rfq
	ELJ-PE2N7KF Panasonic	FIXED IND 2.7NH 2.1A 30 MOHM SMD	0
	ELL-SFG4R7NA Panasonic	FIXED IND 4.7UH 1.1A 130 MOHM	0
	ELL-6RH820M Panasonic	FIXED IND 82UH 350MA 870 MOHM	0
	ELC-06D151E Panasonic	FIXED IND 150UH 450MA 370 MOHM	0
	ELL-4LG100MA Panasonic	FIXED IND 10UH 950MA 200 MOHM	0
	ELC-16B682L Panasonic	FIXED IND 6.8MH 320MA 4.2 OHM TH	0
	ELJ-PC4R7MF3 Panasonic	FIXED IND 4.7UH 610MA 250 MOHM	0
	ELJ-RF4N7DFB Panasonic	FIXED IND 4.7NH 360MA 170 MOHM	0
	ELJ-NAR68KF Panasonic	FIXED IND 680NH 155MA 1.7 OHM	0
	ELJ-PE2N7KFA Panasonic	FIXED IND 2.7NH 2.1A 30 MOHM SMD	0
	ELC-12E6R8L Panasonic	FIXED IND 6.8UH 3.9A 18 MOHM TH	0
	ELC-10D471E Panasonic	FIXED IND 470UH 700MA 450 MOHM	0
	ELC-12D222E Panasonic	FIXED IND 2.2MH 600MA 1.5 OHM TH	0
	ELJ-NC22NKF Panasonic	FIXED IND 22NH 240MA 430 MOHM	0
	ELC-16B222L Panasonic	FIXED IND 2.2MH 570MA 1.38 OHM	0
	ELC-09D3R3F Panasonic	FIXED IND 3.3UH 3.2A 15 MOHM TH	0
	ELC-09D681F Panasonic	FIXED IND 680UH 340MA 1.4 OHM TH	0
	ELJ-RER12JFA Panasonic	FIXED IND 120NH 130MA 3 OHM SMD	0
	ELC-16B220L Panasonic	FIXED IND 22UH 4.6A 31 MOHM TH	0
	ELJ-ND56NKF Panasonic	FIXED IND 56NH 360MA 510 MOHM	0

Fixed Inductors

1. Overview

Fixed inductors are passive electronic components designed to store energy in magnetic fields when electrical current flows through them. Unlike variable inductors, their inductance values remain constant during operation. These components play critical roles in filtering, signal processing, energy storage, and electromagnetic interference (EMI) suppression across modern electronics, including power supplies, communication systems, and automotive electronics.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Wirewound Inductors	High precision, high current handling, low resistance	Power supplies, DC-DC converters
Chip Inductors	Compact SMD package, stable performance at high frequencies	Mobile devices, RF circuits
Ferrite Bead Inductors	Effective high-frequency noise suppression	EMI filtering in digital circuits
Thin-Film Inductors	Ultra-compact, high Q-factor, tight tolerance	5G communication modules, IoT devices

3. Structure and Composition

Typical fixed inductors consist of:

Magnetic Core: Made from ferrite, powdered iron, or composite materials to concentrate magnetic flux
Coil Structure: Copper wire wound around the core (enamelled or silver-plated)
Encapsulation: Molded resin or ceramic coating for mechanical protection and insulation
Terminations: Solder-coated ends for PCB mounting (for SMD types) or leaded connections

4. Key Technical Specifications

Parameter	Description	Importance
Inductance (L)	Measured in henrys (H), determines energy storage capacity	Defines filtering/energy storage performance
Rated Current (I_rated)	Maximum DC current before saturation	Prevents core saturation and failure
DC Resistance (DCR)	Resistance of coil windings	Affects efficiency and thermal performance
Self-Resonant Frequency (SRF)	Frequency where inductor behaves as capacitor	Limits effective operating frequency range
Q Factor	Quality factor indicating efficiency	Higher Q = lower energy losses

5. Application Fields

Consumer Electronics: Smartphones, laptops, LED drivers
Industrial Equipment: Motor drives, power inverters
Automotive Systems: ECU modules, EV battery management
Telecom Infrastructure: Base station filters, optical transceivers

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Murata	LQH3NPN100M	10 H, 1.2A, 1.8 1.4mm chip inductor
TDK	MLZ2012A100T	100MHz SRF, 1.0 1.25mm for RF circuits
Vishay	IHLP2525CZER1R0M	1 H, 12A, composite construction
Coilcraft	0402DC-103J	10 H, 5% tolerance, ultra-low profile

7. Selection Guidelines

Key considerations during selection:

Calculate required inductance based on switching frequency and ripple current
Verify rated current exceeds maximum operating current by 20-30%
Select SRF higher than circuit operating frequency
Consider package size vs. thermal dissipation requirements
For EMI suppression: Choose ferrite beads with impedance curves matching target frequencies

8. Industry Trends

Current development trends include:

Miniaturization: Sub-0.5mm size inductors for wearable devices
High-Frequency Operation: Components supporting >10GHz 5G applications
Integrated Solutions: Combined inductor-filter modules
Material Innovation: Nanocrystalline cores for higher saturation flux
Automotive Focus: AEC-Q qualified parts for EV/HEV systems