Fixed Inductors

Part Number	Description / PDF	Quantity
B82432C1123K000 TDK EPCOS	FIXED IND 12UH 300MA 1.1 OHM SMD	0
B82559A0242A013 TDK EPCOS	FIXED IND 2.4UH 16.5A 2.76 MOHM	499
B82442A1564J000 TDK EPCOS	FIXED IND 560UH 110MA 6.8 OHM	0
B82473M1154K000 TDK EPCOS	FIXED IND 150UH 580MA 640 MOHM	0
B82462A4105K000 TDK EPCOS	FIXED IND 1MH 110MA 13 OHM SMD	14834
B82477P4682M000 TDK EPCOS	FIXED IND 6.8UH 6.6A 15 MOHM SMD	1155
B82432T1153K000 TDK EPCOS	FIXED IND 15UH 600MA 500 MOHM	7349
B82476B1103M100 TDK EPCOS	FIXED IND 10UH 4.3A 27 MOHM SMD	271
B82559B7103A016 TDK EPCOS	FIXED IND 10UH 13A 7.2 MOHM SMD	533
B82442H1333K000 TDK EPCOS	FIXED IND 33UH 560MA 500 MOHM	793
B82131A5152M000 TDK EPCOS	FIXED IND 6UH 1.5A 190 MOHM TH	2478
B78108E1153K000 TDK EPCOS	FIXED IND 15UH 1.6A 230 MOHM TH	542
B82442T1475J50 TDK EPCOS	FIXED IND 4.7MH 73MA 48.6 OHM	0
B82442T1823K050 TDK EPCOS	FIXED IND 82UH 540MA 832 MOHM	0
B78108S1564J000 TDK EPCOS	FIXED IND 560UH 160MA 8.8 OHM TH	7174
B82562N4334M000 TDK EPCOS	FIXED IND 330UH 490MA 920 MOHM	0
B82144F2122K000 TDK EPCOS	FIXED IND 1.2UH 4.25A 44 MOHM TH	2381
B82442T1824K050 TDK EPCOS	FIXED IND 820UH 170MA 7.86 OHM	0
B82477R4302M100 TDK EPCOS	FIXED IND 3UH 8.7A 9 MOHM SMD	0
B82477R4472M100 TDK EPCOS	FIXED IND 4.7UH 7.85A 11 MOHM	249

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