Fixed Inductors

Part Number	Description / PDF	Quantity
B82496C3339A000 TDK EPCOS	FIXED IND 3.3NH 1.2A 60 MOHM SMD	10568
B82144F2562K000 TDK EPCOS	FIXED IND 5.6UH 2.95A 90 MOHM TH	1203
B82496C3270G000 TDK EPCOS	FIXED IND 27NH 360MA 550 MOHM	5111
B82476B1472M100 TDK EPCOS	FIXED IND 4.7UH 5.3A 16.5 MOHM	5629
B82477P4154M000 TDK EPCOS	FIXED IND 150UH 1.61A 185 MOHM	307
B82498F3220G000 TDK EPCOS	FIXED IND 22NH 700MA 80 MOHM SMD	0
B82144A2105J000 TDK EPCOS	FIXED IND 1MH 200MA 3.8 OHM TH	0
B82144F2274J000 TDK EPCOS	FIXED IND 270UH 800MA 1.2 OHM TH	2386
B82472P6104M000 TDK EPCOS	FIXED IND 100UH 670MA 390 MOHM	3
B82498F3150G000 TDK EPCOS	FIXED IND 15NH 650MA 130 MOHM	0
B82442H1824J000 TDK EPCOS	FIXED IND 820UH 130MA 10.4 OHM	0
B82422A3820J100 TDK EPCOS	FIXED IND 82NH 450MA 240 MOHM	0
B82498F3279K000 TDK EPCOS	FIXED IND 2.7NH 1A 30 MOHM SMD	1865
B82498F1272J000 TDK EPCOS	FIXED IND 2.7UH 120MA 2 OHM SMD	0
B82559A7103A020 TDK EPCOS	FIXED IND 10UH 3.9 MOHM SMD	957
B82476B1683M100 TDK EPCOS	FIXED IND 68UH 1.65A 160 MOHM	265
B82476A1473M000 TDK EPCOS	FIXED IND 47UH 1.8A 120 MOHM SMD	2468
B82472G4472M000 TDK EPCOS	FIXED IND 4.7UH 2.3A 43 MOHM SMD	2244
B78148E1473J000 TDK EPCOS	FIXED IND 47UH 950MA 680 MOHM TH	865
B82144B2394J000 TDK EPCOS	FIXED IND 390UH 650MA 1.72 OHM	3425

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