Fixed Inductors

Part Number	Description / PDF	Quantity
HF1008R-271G API Delevan	FIXED IND 270NH 345MA 1.25 OHM	0
S1210-181F API Delevan	FIXED IND 180NH 934MA 220 MOHM	0
ER1025-12KS API Delevan	FIXED IND 470NH 650MA 350 MOHM	0
HF1008-182K API Delevan	FIXED IND 1.8UH 305MA 1.6 OHM	0
S1812R-103G API Delevan	FIXED IND 10UH 333MA 1.8 OHM SMD	0
8532R-07K API Delevan	FIXED IND 3.3UH 4.7A 16 MOHM SMD	0
1210-153F API Delevan	FIXED IND 15UH 257MA 2.8 OHM SMD	0
P1812R-563G API Delevan	FIXED IND 56UH 240MA 2.268 OHM	0
S1812R-153J API Delevan	FIXED IND 15UH 301MA 2.2 OHM SMD	0
SP1210R-334K API Delevan	FIXED IND 330UH 88MA 26.8 OHM	0
SPD127R-154M API Delevan	FIXED IND 150UH 1.4A 320 MOHM	431
4922-221L API Delevan	FIXED IND 220NH 7A 8 MOHM SMD	0
1210R-272J API Delevan	FIXED IND 2.7UH 411MA 1.1 OHM	888
5022R-152G API Delevan	FIXED IND 1.5UH 855MA 500 MOHM	0
SP1210R-224J API Delevan	FIXED IND 220UH 100MA 20.7 OHM	0
P1812R-102H API Delevan	FIXED IND 1UH 1.05A 113 MOHM SMD	0
HF1008R-150K API Delevan	FIXED IND 15NH 1.053A 110 MOHM	0
S1210R-153F API Delevan	FIXED IND 15UH 254MA 2.5 OHM SMD	0
5022-163F API Delevan	FIXED IND 16UH 420MA 1.8 OHM SMD	0
103-100M API Delevan	FIXED IND 10NH 1.27A 60 MOHM SMD	0

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