Fixed Inductors

Part Number	Description / PDF	Quantity
ELL-6RH1R5M Panasonic	FIXED IND 1.5UH 2.4A 24 MOHM SMD	369
ELC-18E820L Panasonic	FIXED IND 82UH 3.5A 40 MOHM TH	0
ELL-4FG330MA Panasonic	FIXED IND 33UH 400MA 1.06 OHM	5669
ELL-4LG6R2NA Panasonic	FIXED IND 6.2UH 1.1A 140 MOHM	3921
ELJ-PE12NKF Panasonic	FIXED IND 12NH 1.3A 80 MOHM SMD	989
ELJ-NC39NJF Panasonic	FIXED IND 39NH 215MA 550 MOHM	2816
ELJ-QF2N2ZF Panasonic	FIXED IND 2.2NH 400MA 90 MOHM	19037
ELL-6GM560M Panasonic	FIXED IND 56UH 380MA 700 MOHM	873
ELL-6PM820M Panasonic	FIXED IND 82UH 360MA 680 MOHM	413
ETQ-P3WR33WFN Panasonic	FIXED IND 330NH 21A 3.9 MOHM SMD	9
ETQ-P3M1R0KVP Panasonic	FIXED IND 1UH 9A 10.56 MOHM SMD	0
ELC-18E392 Panasonic	FIXED IND 3.9MH 500MA 1.1 OHM TH	0
ELJ-EA151KF Panasonic	FIXED IND 150UH 45MA 3.1 OHM SMD	18643
ELC-18E220 Panasonic	FIXED IND 22UH 5A 22 MOHM TH	0
ELL-6RH560M Panasonic	FIXED IND 56UH 450MA 540 MOHM	1275
ELJ-PE5N6KF Panasonic	FIXED IND 5.6NH 2.1A 55 MOHM SMD	221
ELJ-SA150KF Panasonic	FIXED IND 15UH 15MA 2.2 OHM SMD	1
ELC-3FN7R5N Panasonic	FIXED IND 7.5UH 600MA 390 MOHM	2523
ELJ-QF39NGF Panasonic	FIXED IND 39NH 150MA 1.7 OHM SMD	15049
ETQ-P4M220YFN Panasonic	FIXED IND 22UH 2.9A 138.8 MOHM	144

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