Fixed Inductors

Part Number	Description / PDF	Quantity
B82442T1565K000 TDK EPCOS	FIXED IND 5.6MH 66MA 54.7 OHM	0
B82111E0000C029 TDK EPCOS	FIXED IND 1.2MH 100MA 34 OHM TH	0
B82422A3101K100 TDK EPCOS	FIXED IND 100NH 440MA 260 MOHM	11591
B82422A1123K100 TDK EPCOS	FIXED IND 12UH 175MA 1.65 OHM	1804
B82144F2332K000 TDK EPCOS	FIXED IND 3.3UH 3.5A 65 MOHM TH	2377
B82498F3689J001 TDK EPCOS	FIXED IND 6.8NH 800MA 50 MOHM	0
B82442T1823K000 TDK EPCOS	FIXED IND 82UH 540MA 832 MOHM	0
B82477R4474M100 TDK EPCOS	FIXED IND 470UH 1.07A 605 MOHM	3695
B82144F2152K000 TDK EPCOS	FIXED IND 1.5UH 4.1A 45 MOHM TH	1950
B82477D6223M603 TDK EPCOS	FIXED IND 22UH 3.85A 53MOHM SMD	500
B82464A4334K000 TDK EPCOS	FIXED IND 330UH 580MA 1 OHM SMD	361
B82442A1155K000 TDK EPCOS	FIXED IND 1.5MH 70MA 16 OHM SMD	4097
B82477G4153M000 TDK EPCOS	FIXED IND 15UH 4.5A 27 MOHM SMD	290
B82422A1562J100 TDK EPCOS	FIXED IND 5.6UH 140MA 2.6 OHM	4991
B82132A5202M000 TDK EPCOS	FIXED IND 6UH 2A 110 MOHM TH	1747
B82559B3152A016 TDK EPCOS	FIXED IND 1.5UH 30A 1.4 MOHM SMD	559
B78108S1122K000 TDK EPCOS	FIXED IND 1.2UH 1.15A 180 MOHM	5829
B82482M1152N000 TDK EPCOS	PCM120T-1R5N-D; 12.4X13.1X11.5 M	0
B78148E1223K009 TDK EPCOS	FIXED IND 22UH 1.3A 105 MOHM TH	0
B82144F2333J000 TDK EPCOS	FIXED IND 33UH 1.9A 220 MOHM TH	1077

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