Fixed Inductors

Part Number	Description / PDF	Quantity
VCTA32251B-R47MS6 Delta Electronics	FIXED IND 470NH 4.6A 22 MOHM SMD	1294
SDED20161T-1R0MS Delta Electronics	FIXED IND 1UH 1.7A 107MOHM SMD	4000
0402HM-120EGTS Delta Electronics	FIXED IND 12NH 500MA 140 MOHM	5219
0805CT-100EKTS Delta Electronics	FIXED IND 10NH 800MA 80 MOHM SMD	2847
HMLQ32251T-4R7MS Delta Electronics	FIXED IND 4.7UH 1.7A 240MOHM SMD	3672
0402HP-110EGTS Delta Electronics	FIXED IND 11NH 1.4A 65 MOHM SMD	7140
CML0306-4N3-HNH Delta Electronics	FIXED IND 4.3NH 300MA 400 MOHM	0
0402HP-270EJTS Delta Electronics	FIXED IND 27NH 450MA 275 MOHM	7835
0805CS-681EJTS Delta Electronics	FIXED IND 680NH 190MA 2.2 OHM	1915
0402HP-150EJTS Delta Electronics	FIXED IND 15NH 1.1A 110 MOHM SMD	7850
0402HS-121EKTS Delta Electronics	FIXED IND 120NH 50MA 2.66OHM SMD	7990
0402HP-190EKTS Delta Electronics	FIXED IND 19NH 850MA 145MOHM SMD	7975
0402HS-720EJTS Delta Electronics	FIXED IND 72NH 100MA 1.12OHM SMD	7510
0805CS-601EJTS Delta Electronics	FIXED IND 600NH 450MA 1.6 OHM	1701
0402HM-4N1EBTS Delta Electronics	FIXED IND 4.1NH 750MA 70MOHM SMD	7920
0402HM-120EKTS Delta Electronics	FIXED IND 12NH 500MA 140MOHM SMD	7990
HMLB25201B-R47MSR Delta Electronics	FIXED IND 470NH 4.5A 26MOHM SMD	8314
0402HM-130EGTS Delta Electronics	FIXED IND 13NH 430MA 210 MOHM	3332
CML0306-9N1-JNH Delta Electronics	FIXED IND 9.1NH 180MA 1.2 OHM	0
0402HC-2N4EDTS Delta Electronics	FIXED IND 2.4NH 1A 27 MOHM SMD	7990

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