Fixed Inductors

Part Number	Description / PDF	Quantity
0402HM-4N3EJTS Delta Electronics	FIXED IND 4.3NH 750MA 70 MOHM	8000
0402HP-200EJTS Delta Electronics	FIXED IND 20NH 780MA 185 MOHM	7900
0805CT-3N9EKTS Delta Electronics	FIXED IND 3.9NH 800MA 60MOHM SMD	3968
0402HM-8N2EDTS Delta Electronics	FIXED IND 8.2NH 540MA 140 MOHM	7987
0805CT-220EKTS Delta Electronics	FIXED IND 22NH 800MA 150MOHM SMD	3994
0805CS-271EKFS Delta Electronics	FIXED IND 270NH 700MA 300 MOHM	3900
0805CS-680EKTS Delta Electronics	FIXED IND 68NH 500MA 380 MOHM	3938
SDED20161T-150MS Delta Electronics	FIXED IND 15UH 420MA 1.895OHM SM	3790
0805CS-911EKTS Delta Electronics	FIXED IND 910NH 170MA 1.9 OHM	3902
0805CS-201EJTS Delta Electronics	FIXED IND 200NH 400MA 660 MOHM	3890
0402HP-9N0EHTS Delta Electronics	FIXED IND 9NH 1.4A 80 MOHM SMD	7995
SDEB12101T-R47MSD Delta Electronics	FIXED IND 470NH 1.55A 96MOHM SMD	3960
0402HM-240EKTS Delta Electronics	FIXED IND 24NH 280MA 520MOHM SMD	7990
0402HM-220EKTS Delta Electronics	FIXED IND 22NH 310MA 300MOHM SMD	8000
0402HM-121EKTS Delta Electronics	FIXED IND 120NH 110MA 2.66 OHM	6475
0402HM-7N5EDTS Delta Electronics	FIXED IND 7.5NH 570MA 130 MOHM	7920
0402HC-2N4ECTS Delta Electronics	FIXED IND 2.4NH 1A 27 MOHM SMD	7764
0402HP-8N2EKTS Delta Electronics	FIXED IND 8.2NH 1.5A 58 MOHM SMD	7800
0402HP-250EJTS Delta Electronics	FIXED IND 25NH 600MA 250 MOHM	7885
0805CT-470EJTS Delta Electronics	FIXED IND 47NH 600MA 390 MOHM	3797

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