Fixed Inductors

Part Number	Description / PDF	Quantity
SDEM25201B-2R2MS Delta Electronics	FIXED IND 2.2UH 2.05A 117MOHM SM	3344
0805CT-1N8EJTS Delta Electronics	FIXED IND 1.8NH 800MA 30 MOHM	11478
0402HS-270EGTS Delta Electronics	FIXED IND 27NH 400MA 300 MOHM	2835
0805CS-821EKTS Delta Electronics	FIXED IND 820NH 180MA 2.35 OHM	3970
0805CS-751EKTS Delta Electronics	FIXED IND 750NH 180MA 2.3 OHM	3978
0805CS-3N3EJTS Delta Electronics	FIXED IND 3.3NH 600MA 80 MOHM	5937
0805CS-182EGTS Delta Electronics	FIXED IND 1.8UH 170MA 2.5 OHM	3750
0402HP-1N0ECTS Delta Electronics	FIXED IND 1NH 2.3A 30 MOHM SMD	6773
0805CT-102EKFS Delta Electronics	FIXED IND 1UH 450MA 900 MOHM SMD	3480
0402HS-330EJTS Delta Electronics	FIXED IND 33NH 400MA 350 MOHM	7965
HMLE32251B-2R2MS Delta Electronics	FIXED IND 2.2UH 2.5A 90MOHM SMD	1451
0805CS-821EGTS Delta Electronics	FIXED IND 820NH 180MA 2.35 OHM	3402
0805CS-180EJTS Delta Electronics	FIXED IND 18NH 600MA 200 MOHM	3990
0402HP-300EGTS Delta Electronics	FIXED IND 30NH 450MA 330 MOHM	7095
0402HP-2N4ECTS Delta Electronics	FIXED IND 2.4NH 2A 42 MOHM SMD	7765
0402HM-7N3EHTS Delta Electronics	FIXED INDUCTOR 7.3NH 570MA SMD	7975
0402HM-7N3EDTS Delta Electronics	FIXED INDUCTOR 7.3NH 570MA SMD	8000
0805CS-201EKTS Delta Electronics	FIXED IND 200NH 400MA 660 MOHM	3995
0402HM-5N1ECTS Delta Electronics	FIXED IND 5.1NH 600MA 120 MOHM	7990
SDET25201T-1R5MS Delta Electronics	FIXED IND 1.5UH 1.7A 114MOHM SMD	4900

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