Fixed Inductors

Part Number	Description / PDF	Quantity
AX97-408R2 Triad Magnetics	FIXED IND 8.2UH 7A 20 MOHM SMD	0
FIT44-3-B Triad Magnetics	FIXED IND 12.3UH 4A 23.4 MOHM TH	0
FIRCH-5 Triad Magnetics	FIXED IND 5.9UH 5.7A 18.5 MOHM	200
FIT44-2 Triad Magnetics	FIXED IND 14.75UH 3.4A 30.7 MOHM	5871041
FIT106-6 Triad Magnetics	FIXED IND 70.05UH 9.7A 24 MOHM	2357960
AX97-40331 Triad Magnetics	FIXED IND 330UH 1.1A 450 MOHM	0
FIRCH-6-B Triad Magnetics	FIXED IND 7.22UH 4.8A 26.1 MOHM	0
RC-8-B Triad Magnetics	FIXED IND 250UH 1.25A 210 MOHM	648
FIT80-1-B Triad Magnetics	FIXED IND 128UH 4A 95.2 MOHM TH	864
AX97-10220 Triad Magnetics	FIXED IND 22UH 700MA 430 MOHM	0
AX97-20221 Triad Magnetics	FIXED IND 220UH 400MA 1.3 OHM	0
AX104R-101 Triad Magnetics	FIXED IND 100UH 1.35A 304 MOHM	0
AX97-40220 Triad Magnetics	FIXED IND 22UH 4.4A 40 MOHM SMD	0
FIT50-5 Triad Magnetics	FIXED IND 16.76UH 5.7A 20 MOHM	47912
AX02-302R2-T Triad Magnetics	FIXED IND 2.2UH 12A 5.1 MOHM	375
FIT44-1 Triad Magnetics	FIXED IND 18.85UH 2.8A 44.8 MOHM	74222
C-14X Triad Magnetics	FIXED IND 6H 200MA 150 OHM CHASS	17868
AX97-20220 Triad Magnetics	FIXED IND 22UH 1.3A 150 MOHM SMD	0
AX97-301R0 Triad Magnetics	FIXED IND 1UH 8.5A 10 MOHM SMD	0
AX97-40150 Triad Magnetics	FIXED IND 15UH 5.3A 30 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