Fixed Inductors

Part Number	Description / PDF	Quantity
FIT44-1-B Triad Magnetics	FIXED IND 18.85UH 2.8A 44.8 MOHM	29568
C-56U Triad Magnetics	FIXED IND 35MH 2A 790 MOHM CHASS	164145
FIT68-2 Triad Magnetics	FIXED IND 71.1UH 3.4A 86.1 MOHM	837
AX02-301R5-T Triad Magnetics	FIXED IND 1.5UH 18A 2.3 MOHM	379
FIT50-4 Triad Magnetics	FIXED IND 21.65UH 4.8A 29.2 MOHM	1821915
AX97-306R8 Triad Magnetics	FIXED IND 6.8UH 5.2A 30 MOHM	350
AX104R-1R5 Triad Magnetics	FIXED IND 1.5UH 6.5A 8.1 MOHM	0
C-3X Triad Magnetics	FIXED IND 10H 50MA 500 OHM CHASS	21
FIT50-1-B Triad Magnetics	FIXED IND 47.4UH 2.8A 78.9 MOHM	0
AX97-20330 Triad Magnetics	FIXED IND 33UH 1.1A 210 MOHM SMD	0
FIT68-2-B Triad Magnetics	FIXED IND 71.1UH 3.4A 86.1 MOHM	0
AX97-30470 Triad Magnetics	FIXED IND 47UH 2A 160 MOHM SMD	350
AX02-301R5 Triad Magnetics	FIXED IND 1.5UH 18A 2.3 MOHM SMD	0
FIT50-2 Triad Magnetics	FIXED IND 35.48UH 3.4A 57.8 MOHM	465990
FIT80-4 Triad Magnetics	FIXED IND 65.04UH 6.8A 32.8 MOHM	378
AX97-30102 Triad Magnetics	FIXED IND 1MH 300MA 3.15 OHM SMD	350
1412C1-RF Triad Magnetics	FIXED INDUCTOR 56UH 30A	0
FIE220-1-B Triad Magnetics	FIXED IND 11.7UH 120A 1 MOHM TH	0
FIE220-1 Triad Magnetics	FIXED IND 11.7UH 120A 1 MOHM TH	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