Fixed Inductors

Part Number	Description / PDF	Quantity
103-561K API Delevan	FIXED IND 560NH 590MA 278 MOHM	0
HF1008-391J API Delevan	FIXED IND 390NH 320MA 1.45 OHM	0
P1330R-564H API Delevan	FIXED IND 560UH 138MA 6.96 OHM	0
1641R-104K API Delevan	FIXED IND 100UH 164MA 3.12 OHM	352
S1812R-683J API Delevan	FIXED IND 68UH 215MA 4.3 OHM SMD	0
SP1210R-272H API Delevan	FIXED IND 2.7UH 826MA 305 MOHM	0
P1812R-122J API Delevan	FIXED IND 1.2UH 1A 199 MOHM SMD	0
8532-40H API Delevan	FIXED IND 1.8MH 300MA 4 OHM SMD	0
1025R-82K API Delevan	FIXED IND 390UH 40MA 35 OHM TH	0
ER1025-00KS API Delevan	FIXED IND 150NH 1.2A 100 MOHM TH	0
HF1008R-150M API Delevan	FIXED IND 15NH 1.053A 110 MOHM	0
0819-58H API Delevan	FIXED IND 27UH 100MA 4.7 OHM TH	0
SP1812R-473H API Delevan	FIXED IND 47UH 335MA 1.8 OHM SMD	0
P1812R-222J API Delevan	FIXED IND 2.2UH 850MA 268 MOHM	0
5500R-684K API Delevan	FIXED IND 680UH 1.32A 570 MOHM	30
HF1008-152J API Delevan	FIXED IND 1.5UH 315MA 1.5 OHM	0
1812R-563G API Delevan	FIXED IND 56UH 191MA 5.5 OHM SMD	0
P1812R-184J API Delevan	FIXED IND 180UH 120MA 8.4 OHM	0
1812R-684H API Delevan	FIXED IND 680UH 82MA 30 OHM SMD	0
SP1008R-222K API Delevan	FIXED IND 2.2UH 509MA 437 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