Fixed Inductors

Part Number	Description / PDF	Quantity
ELJ-QF16NJF Panasonic	FIXED IND 16NH 240MA 650 MOHM	17225
ELT-5KT3R3MB Panasonic	FIXED IND 3.3UH 1A 170 MOHM SMD	1336
ELJ-QF3N6DF Panasonic	FIXED IND 3.6NH 380MA 140 MOHM	16624
ELL-5PS560M Panasonic	FIXED IND 56UH 500MA 680 MOHM	675
ELJ-SC560KF Panasonic	FIXED IND 56UH 10MA 7.1 OHM SMD	1833
ELJ-PC220MF3 Panasonic	FIXED IND 22UH 275MA 1.22 OHM	1
ELL-6PM120M Panasonic	FIXED IND 12UH 950MA 110 MOHM	777
ELL-5PS150M Panasonic	FIXED IND 15UH 1A 170 MOHM SMD	2133
ELC-18E5R6L Panasonic	FIXED IND 5.6UH 6.7A 11 MOHM TH	0
ELL-6GM270M Panasonic	FIXED IND 27UH 560MA 350 MOHM	965
ELC-18E470L Panasonic	FIXED IND 47UH 4.1A 30 MOHM TH	0
ELL-6GM5R6N Panasonic	FIXED IND 5.6UH 1.2A 86 MOHM SMD	254
ELG-TEA1R5NA Panasonic	FIXED IND 1.5UH 1A 180 MOHM SMD	3331
ELL-8TP820MB Panasonic	FIXED IND 82UH 1.15A 170 MOHM	1096
ELJ-QF2N4ZF Panasonic	FIXED IND 2.4NH 400MA 100 MOHM	17821
ELJ-FBR56MF Panasonic	FIXED IND 560NH 560MA 420 MOHM	1817
ELL-4GG5R6N Panasonic	FIXED IND 5.6UH 970MA 170 MOHM	122202
ETQ-P3M3R3YFP Panasonic	FIXED IND 3.3UH 5A 34.4 MOHM SMD	0
ELJ-PC120KF Panasonic	FIXED IND 12UH 195MA 2.7 OHM SMD	509
ELL-ATV5R1N Panasonic	FIXED IND 5.1UH 4.35A 14 MOHM	12

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