Fixed Inductors

Image	Part Number	Description / PDF	Quantity	Rfq
	ELC-10E122L Panasonic	FIXED IND 1.2MH 290MA 2 OHM TH	0
	ELJ-FC390KF Panasonic	FIXED IND 39UH 90MA 9.5 OHM SMD	0
	ELJ-FC560KF Panasonic	FIXED IND 56UH 75MA 12.1 OHM SMD	0
	ELJ-FB100JF Panasonic	FIXED IND 10UH 235MA 1.8 OHM SMD	0
	ELC-15E470 Panasonic	FIXED IND 47UH 3.7A 37 MOHM TH	0
	ELC-16B821L Panasonic	FIXED IND 820UH 880MA 580 MOHM	0
	ELJ-PB220KF Panasonic	FIXED IND 22UH 300MA 1 OHM SMD	0
	ELJ-RE33NGF2 Panasonic	FIXED IND 33NH 300MA 600 MOHM	0
	ELJ-PA6R8MF2 Panasonic	FIXED IND 6.8UH 620MA 280 MOHM	0
	ELC-10D680E Panasonic	FIXED IND 68UH 2.1A 75 MOHM TH	0
	ELJ-ND47NJF Panasonic	FIXED IND 47NH 385MA 460 MOHM	0
	ELC-09D3R9DF Panasonic	FIXED IND 3.9UH 3.1A 16 MOHM TH	0
	ELJ-NDR12JF Panasonic	FIXED IND 120NH 275MA 990 MOHM	0
	ELC-15E222 Panasonic	FIXED IND 2.2MH 630MA 1.1 OHM TH	0
	ELL-5PM180M Panasonic	FIXED IND 18UH 720MA 180 MOHM	0
	ELJ-PE12NKFA Panasonic	FIXED IND 12NH 1.3A 80 MOHM SMD	0
	ELL-4LM180M Panasonic	FIXED IND 18UH 460MA 320 MOHM	0
	ELJ-PB101KF Panasonic	FIXED IND 100UH 150MA 4 OHM SMD	0
	ELC-12E101L Panasonic	FIXED IND 100UH 1.3A 140 MOHM TH	0
	ELL-CTV390M Panasonic	FIXED IND 39UH 2.1A 61 MOHM SMD	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