Fixed Inductors

Image	Part Number	Description / PDF	Quantity	Rfq
	41101C Murata Power Solutions	FIXED IND 100UH 1.47A 158 MOHM	0
	472R2SC Murata Power Solutions	FIXED IND 2.2UH 7A 8.5 MOHM SMD	0
	414R7C Murata Power Solutions	FIXED IND 4.7UH 6.7A 18 MOHM	0
	43212C-R Murata Power Solutions	FIXED IND 2.1UH 21A 2.22 MOHM	0
	41100C Murata Power Solutions	FIXED IND 10UH 4.7A 24 MOHM SMD	0
	42212C-R Murata Power Solutions	FIXED IND 2.1UH 11.5A 3.8 MOHM	0
	29L154C Murata Power Solutions	FIXED IND 150UH 430MA 850 MOHM	0
	28684C Murata Power Solutions	FIXED IND 680UH 640MA 1.17 OHM	0
	29L104C Murata Power Solutions	FIXED IND 100UH 480MA 456 MOHM	0
	28682C Murata Power Solutions	FIXED IND 6.8UH 6.8A 14 MOHM SMD	0
	18682C Murata Power Solutions	FIXED IND 6.8UH 4.15A 12 MOHM	0
	404R7C Murata Power Solutions	FIXED IND 4.7UH 4.4A 19 MOHM	0
	29L684C Murata Power Solutions	FIXED IND 680UH 200MA 3.61 OHM	0
	18224C Murata Power Solutions	FIXED IND 220UH 900MA 230 MOHM	0
	34L223C Murata Power Solutions	FIXED IND 22UH 480MA 780 MOHM	0
	18335C Murata Power Solutions	FIXED IND 3.3MH 220MA 3.5 OHM TH	0
	18103C Murata Power Solutions	FIXED IND 10UH 3.45A 15 MOHM TH	0
	28335C Murata Power Solutions	FIXED IND 3.3MH 290MA 5.76 OHM	0
	34L682C Murata Power Solutions	FIXED IND 6.8UH 680MA 265 MOHM	0
	28105C Murata Power Solutions	FIXED IND 1MH 510MA 1.82 OHM 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