Fixed Inductors

Part Number	Description / PDF	Quantity
AIMC-0805-2N7S-T Abracon	FIXED IND 2.7NH 600MA 100 MOHM	10705
CBC2016T100K TAIYO YUDEN	FIXED IND 10UH 350MA 1.066 OHM	3673
7443556450 Würth Elektronik Midcom	FIXED IND 4.5UH 20.5A 3.4 MOHM	0
MLG0603P2N4ST000 TDK Corporation	FIXED IND 2.4NH 500MA 200 MOHM	19890
744778168 Würth Elektronik Midcom	FIXED IND 68UH 740MA 520 MOHM	571
LMCI1005-18NJT Venkel LTD	FIXED IND 18NH 300MA 600MOHM SMD	0
SPM10040T-R68M-HZ TDK Corporation	FIXED IND 680NH 30A 2.67MOHM SMD	791
LQW15AN22NJ00D TOKO / Murata	FIXED IND 22NH 310MA 300 MOHM	34007
S1812R-821H API Delevan	FIXED IND 820NH 614MA 530 MOHM	0
103-223KS API Delevan	FIXED IND 22UH 125MA 6.4 OHM SMD	0
22R686MC Murata Power Solutions	FIXED IND 68MH 26MA 242 OHM SMD	152239
1210R-331G API Delevan	FIXED IND 330NH 720MA 400 MOHM	0
LQW18AS68NG00D TOKO / Murata	FIXED IND 68NH 600MA 340MOHM SMD	0
0402HS-130EGTS Delta Electronics	FIXED IND 13NH 440MA 210 MOHM	0
B82477G4333M000 TDK EPCOS	FIXED IND 33UH 3A 53 MOHM SMD	1883
RL622-120K-RC J.W. Miller / Bourns	FIXED IND 12UH 2.7A 50 MOHM TH	1879
MEKK2520T2R2M TAIYO YUDEN	FIXED IND 2.2UH 2.4A 97 MOHM SMD	4653
SRP1770TA-3R3M J.W. Miller / Bourns	FIXED IND 3.3UH 28A 3.9 MOHM SMD	786
AISC-1008F-3R3J-T Abracon	FIXED IND 3.3UH 450MA 1.7 OHM	1434
4611-RC J.W. Miller / Bourns	FIXED IND 8.2UH 600MA 1.2 OHM TH	5100

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