Fixed Inductors

Part Number	Description / PDF	Quantity
B82477P2152M000 TDK EPCOS	FIXED IND 1.5UH 8.7A 10 MOHM SMD	600
B82422T1104J000 TDK EPCOS	FIXED IND 100UH 60MA 11 OHM SMD	2883
B82464G4103M000 TDK EPCOS	FIXED IND 10UH 3.4A 30 MOHM SMD	770
B82422T3560J000 TDK EPCOS	FIXED IND 56NH 450MA 210 MOHM	0
B78108E1471M000 TDK EPCOS	FIXED IND 470NH 5A 27 MOHM TH	3231
B82559B7103A019 TDK EPCOS	FIXED IND 10UH 11.7A 8.8 MOHM	438
B82498F3561J001 TDK EPCOS	FIXED IND 560NH 230MA 1.3 OHM	0
B82496C3120G000 TDK EPCOS	FIXED IND 12NH 450MA 350 MOHM	5162
B78108E1473J009 TDK EPCOS	FIXED IND 47UH 950MA 680 MOHM TH	94
B82462A4682M000 TDK EPCOS	FIXED IND 6.8UH 1.4A 100 MOHM	2672
B82559A2102A024 TDK EPCOS	FIXED IND 1UH 54.4A 0.45 MOHM	356
B82479A1104M000 TDK EPCOS	FIXED IND 100UH 1.8A 190 MOHM	5160
B78148S1682K009 TDK EPCOS	FIXED IND 6.8UH 670MA 510 MOHM	0
B82442H1394K000 TDK EPCOS	FIXED IND 390UH 180MA 4.64 OHM	0
B78108E1152K009 TDK EPCOS	FIXED IND 1.5UH 3.8A 47 MOHM TH	4777
B82559B6682A027 TDK EPCOS	FIXED IND 6.8UH 34.5A 1.66 MOHM	494
B82422H1332K008 TDK EPCOS	FIXED IND 3.3UH 770MA 180 MOHM	0
B82422A1472J100 TDK EPCOS	FIXED IND 4.7UH 150MA 2.2 OHM	0
B82422A3100K100 TDK EPCOS	FIXED IND 10NH 750MA 90 MOHM SMD	4044
B82477D6682M603 TDK EPCOS	FIXED IND 6.8UH 6.4A 21MOHM SMD	250

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