Fixed Inductors

Part Number	Description / PDF	Quantity
SP1812R-124G API Delevan	FIXED IND 120UH 210MA 4.6 OHM	0
5022-133G API Delevan	FIXED IND 13UH 520MA 1.2 OHM SMD	0
S1812R-683F API Delevan	FIXED IND 68UH 215MA 4.3 OHM SMD	0
P1330R-102G API Delevan	FIXED IND 1UH 2.78A 35 MOHM SMD	0
1008-101K API Delevan	FIXED IND 100NH 728MA 230 MOHM	0
0819-04H API Delevan	FIXED IND 150NH 760MA 180 MOHM	0
P1330R-224H API Delevan	FIXED IND 220UH 223MA 2.648 OHM	0
1210R-331J API Delevan	FIXED IND 330NH 720MA 400 MOHM	0
SP1812R-393J API Delevan	FIXED IND 39UH 354MA 1.6 OHM SMD	0
1210R-472H API Delevan	FIXED IND 4.7UH 352MA 1.5 OHM	0
M83446/39-29F API Delevan	FIXED IND 2.2UH 535MA 700 MOHM	687
1008-182J API Delevan	FIXED IND 1.8UH 457MA 720 MOHM	0
103-221J API Delevan	FIXED IND 220NH 665MA 220 MOHM	0
2727-10F API Delevan	FIXED IND 56UH 185MA 5.6 OHM TH	0
S1812R-183G API Delevan	FIXED IND 18UH 288MA 2.4 OHM SMD	0
HF1008-390K API Delevan	FIXED IND 39NH 870MA 160 MOHM	0
2727-21J API Delevan	FIXED IND 470UH 84MA 27 OHM TH	0
S1812R-333K API Delevan	FIXED IND 33UH 258MA 3 OHM SMD	2015
5022R-162J API Delevan	FIXED IND 1.6UH 780MA 600 MOHM	0
5022-431F API Delevan	FIXED IND 430NH 1.825A 110 MOHM	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