Fixed Inductors

Image	Part Number	Description / PDF	Quantity	Rfq
	8532R-50J API Delevan	FIXED IND 12MH 120MA 26 OHM SMD	0
	S1812R-821H API Delevan	FIXED IND 820NH 614MA 530 MOHM	0
	103-223KS API Delevan	FIXED IND 22UH 125MA 6.4 OHM SMD	0
	1210R-331G API Delevan	FIXED IND 330NH 720MA 400 MOHM	0
	S1812R-271H API Delevan	FIXED IND 270NH 1.053A 180 MOHM	0
	1812-391F API Delevan	FIXED IND 390NH 535MA 700 MOHM	0
	HF1008-150M API Delevan	FIXED IND 15NH 1.053A 110 MOHM	0
	P1812-333H API Delevan	FIXED IND 33UH 300MA 1.578 OHM	0
	1025R-96K API Delevan	FIXED IND 120NH 1.3A 90 MOHM TH	0
	HF1008R-180J API Delevan	FIXED IND 18NH 965MA 130 MOHM	0
	5022R-151G API Delevan	FIXED IND 150NH 3.5A 30 MOHM SMD	0
	P1330-473G API Delevan	FIXED IND 47UH 467MA 792 MOHM	0
	4590-823K API Delevan	FIXED IND 82UH 3.175A 66 MOHM TH	0
	4590-476K API Delevan	FIXED IND 47MH 140MA 33.7 OHM TH	0
	1210-271G API Delevan	FIXED IND 270NH 759MA 360 MOHM	0
	SP1210-471H API Delevan	FIXED IND 470NH 1.44A 100 MOHM	0
	S1812R-473F API Delevan	FIXED IND 47UH 242MA 3.4 OHM SMD	0
	ER1641-102KS API Delevan	FIXED IND 1UH 1.07A 70 MOHM TH	0
	1812-820M API Delevan	FIXED IND 82NH 700MA 250 MOHM	0
	P1330R-394G API Delevan	FIXED IND 390UH 171MA 5.64 OHM	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